Polyurethane/chitosan/hyaluronic acid scaffolds: providing an optimum environment for fibroblast growth.

OBJECTIVE: Biodegradable polymers can replace damaged tissue components using tissue engineering techniques. The objective of this study is to determine an optimum environment for polymer scaffolds to improve the proliferation of fibroblast cells capable of wound repair. METHOD: In this study, the addition of polysaccharides, such as chitosan (CH) or hyaluronic acid (HA), to a polyurethane (PU) polymer was evaluated using different methods to determine if they affect scaffold morphology and cell activity of fibroblasts prepared from human foreskin tissues. Mechanical properties, such as tensile strength, contact angle and swelling test, were used to check the physical and mechanical properties of the scaffold. Fibroblast growth was also measured at 24, 48 and 72 hours. RESULTS: Scanning electron microscopy (SEM) determined that a 3:1 ratio of PU/CH scaffold, developed by electrospinning, allowed the formation of a uniform structure in scaffold fibres. Physical mechanical tests showed that PU electrospun scaffolds were not modified by the addition of CH. The mean stretch and mean water absorption increased significantly using the PU/CH scaffold, compared with the PU scaffold. However, the mean tensile strength and the mean contact angle, used to study space and porosity, did not differ between scaffolds. Fourier transform infrared spectroscopy confirmed the functional groups (-OH, -NH and -C=O) in the PU/CH scaffold, compared with PU or CH chemical structures alone. HA was then added to CH and PU/CH scaffolds to evaluate the growth of fibroblast cells. Results showed that cell viability and the number of cells, using MTT and trypan blue exclusion assay, respectively, increased significantly at 24, 48 and 72 hours of culture in PU/CH/HA scaffold compared to HA, CH/HA, and PU/HA. Moreover, PU/HA at 48 and 72 hours also increased cell viability and cell numbers compared to HA and CH/HA scaffolds. However, scaffolds at 72 hours had limited space for cell growth. Moreover, SEM data demonstrated that fibroblasts were able to proliferate, penetrate, migrate and survive on PU/HA and PU/CH/HA three-dimensional scaffolds, especially during the first 48 hours. Furthermore, 4',6-diamidino-2-phenylindole (DAPI) staining confirmed that fibroblasts could penetrate PU scaffolds and showed higher cell viability and lower cellular damage in PU/CH/HA, compared to CH/HA and PU/HA scaffolds. Finally, flow cytometry using CD90 and CD105 surface markers revealed that >90% of cells isolated from the human dermis were fibroblasts. CONCLUSION: In summary, PU/HA and PU/CH/HA scaffolds were found to be biocompatible and provided a suitable environment for the growth and proliferation of fibroblasts, which filled and covered all pores between the fibres. The new scaffold used in this study, made of synthetic and natural polymers, is a good candidate for applications in tissue engineering. It is therefore recommended to use PU in grafts or in wound dressing.

Alyssum homolocarpum seed oil (AHSO), containing natural alpha linolenic acid, stearic acid, myristic acid and ß-sitosterol, increases proliferation and differentiation of neural stem cells in vitro.

BACKGROUND: Embryonic neural stem cells (eNSCs) are immature precursors of the central nervous system (CNS), with self-renewal and multipotential differentiation capacities. These are regulated by endogenous and exogenous factors such as alpha-linolenic acid (ALA), a plant-based essential omega-3 polyunsaturated fatty acid. METHODS: In this study, we investigated the effects of various concentrations of Alyssum homolocarpum seed oil (AHSO), containing natural ALA, stearic acid (SA), myristic acid (MA), and ß-sitosterol, on proliferation and differentiation of eNSCs, in comparison to controls and to synthetic pure ALA. RESULTS: Treatment with natural AHSO (25 to 75 µM), similar to synthetic ALA, caused a significant ~ 2-fold increase in eNCSs viability, in comparison to controls. To confirm this proliferative activity, treatment of NSCs with 50 or 75 µM AHSO resulted in a significant increase in mRNA levels of notch1, hes-1 and Ki-67and NICD protein expression, in comparison to controls. Moreover, AHSO administration significantly increased the differentiation of eNSCs toward astrocytes (GFAP+) and oligodendrocytes (MBP+) in a dose dependent manner and was more potent than ALA, at similar concentrations, in comparison to controls. Indeed, only high concentrations of 100 µM AHSO, but not ALA, caused a significant increase in the frequency of neurons (ß-III Tubulin+). CONCLUSION: Our data demonstrated that AHSO, a rich source of ALA containing also other beneficial fatty acids, increased the proliferation and stimulated the differentiation of eNSCs. We suggest that AHSO's effects are caused by ß-sitosterol, SA and MA, present within this oil. AHSO could be used in diet to prevent neurodevelopmental syndromes, cognitive decline during aging, and various psychiatric disorders.

Anti-angiogenic effects of CD73-specific siRNA-loaded nanoparticles in breast cancer-bearing mice.

CD73 facilitates tumor growth by upregulation of the adenosine (immunosuppressive factor) in the tumor microenvironment, however, its precise molecular mechanisms is not precisely understood. Regarding the importance of angiogenesis in tumor development and spreading, we decided to assign the anti-angiogenic effects of CD73 suppression. We used chitosan lactate (ChLa) nanoparticles (NPs) to deliver CD73-specific small interfering RNA (siRNA) into cancer cells. Our results showed that treatment of the 4T1 cells with CD73-specific siRNA-loaded NPs led to potent inhibition of cancer cell proliferation and cell cycle arrest, in vitro. This growth arrest was correlated with downregulation of angiogenesis-related molecules including vascular endothelial growth factor (VEGF)-A, VEGF-R2, interleukin (IL)-6, and transforming growth factor (TGF)-ß. Moreover, administration of NPs loaded with CD73-siRNA into 4T1 breast cancer-bearing mice led to tumor regression and increased mice survival time accompanied with downregulation of angiogenesis (VEGF-A, VEGF-R2, VE-Cadherin, and CD31) and lymphangiogenesis (VEGF-C and LYVE-1)-related genes in the tumor site. Furthermore, the expression of angiogenesis promoting factors including IL-6, TGF-ß, signal transducer, and activator of transcription (STAT)3, hypoxia inducible factor (HIF)-1α, and cyclooxygenase (COX)2 was decreased after the CD73 suppression in mice. Moreover, analysis of leukocytes derived from the tumor samples, spleen, and regional lymph nodes showed that they had lower capability for secretion of angiogenesis promoting factors after CD73-silencing. These results indicate that suppression of tumor development by downregulation of CD73 is in part related to angiogenesis arrest. These findings imply a promising strategy for inhibiting tumor growth accompanied with suppressing the angiogenesis process.

9-cis-Retinoic Acid and 1,25-dihydroxy Vitamin D3 Improve the Differentiation of Neural Stem Cells into Oligodendrocytes through the Inhibition of the Notch and Wnt Signaling Pathways.

BACKGROUND: Differentiating oligodendrocyte precursor cells (OPCs) into oligodendrocytes could be improved by inhibiting signaling pathways such as Wnt and Notch. 9-cis-retinoic acid (9-cis-RA) and 1,25-dihydroxyvitamin D3 (1,25[OH]2D3) can ameliorate oligodendrogenesis. We investigated whether they could increase oligodendrogenesis by inhibiting the Wnt and Notch signaling pathways. METHODS: Cortical neural stem cells were isolated from 14-day-old rat embryos and cultured using the neurosphere assay. The cells were treated in 4 different conditions for 1 week: the negative control group received only the basic fibroblast growth factor, the positive control group received only T3 without growth factors, the RA group was treated with 9-cis-RA, and the Vit D3 group was treated with 1,25(OH)2D3. The effects of 9-cis-RA and 1,25(OH)2D3 on the level of the myelin basic protein (MBP) and the gene expression of the SOX10, MBP gene, HES5, and LRP6 were studied using flow cytometry and real-time PCR. The data were analyzed using one-way ANOVA with GraphPad Prism. A P value less than 0.05 was considered significant. RESULTS: The mRNA expressions of the SOX10, MBP, and MBP gene were significantly increased in the treated groups compared with the negative control group; the increase was similar in the 9-cis-RA group and the positive control group. Furthermore, 9-cis-RA significantly decreased the expression of the HES5 gene, a Notch signaling pathway transcription factor, and 1,25(OH)2D3 significantly reduced the expression of the LRP6 gene, a Wnt signaling pathway co-receptor. CONCLUSION: It seems that 9-cis-RA and 1,25(OH)2D3 are good candidates to improve the differentiation of OPCs into oligodendrocytes.

Melatonin Increases Oligodendrocyte Differentiation in Cultured Neural Stem Cells.

Neural stem cell (NSC) culture is a remarkable tool to investigate the potential therapeutic benefits of drugs in neurological diseases. The purpose of this study was to determine the effect of melatonin on proliferation and differentiation of NSCs in vitro. NSCs were isolated and expanded from mouse embryonic E14 cortex, and the effect of various concentrations of melatonin (0.05, 0.1, 0.5, 1, 5 and 10 µM) on NSC proliferation was assessed by MTT and neurosphere assay. Results showed that melatonin significantly increased NSC viability and NSC proliferation in a dose-dependent manner, in comparison to controls. Similarly, neurosphere formation frequency and cell counts increased significantly with increasing melatonin concentrations and reached its peak at 0.5 µM, in comparison to controls. Moreover, NSCs treated with either low (0.05 µM) or high concentrations (5 µM) of melatonin showed that the mean percentage of glial fibrillary acidic protein (GFAP) positive cells were not significantly different in PDGF or melatonin at 5 µM, in comparison to controls. However, low melatonin concentrations (0.05 µM) showed a slight significant increase in comparison to controls and PDGF. On the other hand, both concentrations of melatonin treatment significantly increased the percentage of myelin basic protein (MBP) positive cells (oligodendrocytes), in comparison to controls and to PDGF. Our results demonstrated, for the first time, that melatonin increased oligodendrocyte differentiation from NSCs. These results suggest that melatonin might have a potential therapeutic effect for some neurological diseases that involve oligodendrocyte and myelin pathologies.

Melatonin exacerbates acute experimental autoimmune encephalomyelitis by enhancing the serum levels of lactate: A potential biomarker of multiple sclerosis progression.

Melatonin has a beneficial role in adult rat models of multiple sclerosis (MS). In this study, melatonin treatment (10 mg/kg/d) was investigated in young age (5-6 weeks old) Lewis rat model of acute experimental autoimmune encephalomyelitis (EAE) followed by assessing serum levels of lactate and melatonin. Results showed that clinical outcomes were exacerbated in melatonin- (neurological score = 6) vs PBS-treated EAE rats (score = 5). Melatonin caused a significant increase in serum IFN-γ, in comparison to PBS-treated EAE rats whereas no considerable change in IL-4 levels were found, although they were significantly lower than those of controls. The ratio of IFN-γ/IL-4, an indicator of Th-1/Th-2, was significantly higher in PBS- and melatonin- treated EAE rats, in comparison to controls. Moreover, results showed increased lymphocyte infiltration, activated astrocytes (GFAP+ cells) but also higher demyelinated plaques (MBP-deficient areas) in the lumbar spinal cord of melatonin-treated EAE rats. Finally, serum levels of lactate, but not melatonin, significantly increased in the melatonin group, compared to untreated EAE and normal rats. In conclusion, our results indicated a relationship between age and the development of EAE since a negative impact was found for melatonin on EAE recovery of young rats by enhancing IFN-γ, the ratio of Th1/Th2 cells, and astrocyte activation, which seems to delay the remyelination process. While melatonin levels decline in MS patients, lactate might be a potential diagnostic biomarker for prediction of disease progression. Early administration of melatonin in the acute phase of MS might be harmful and needs further investigations.

Absence of a role for interleukin-13 in inflammatory bowel disease.

IL-13 has been implicated in the pathogenesis of ulcerative colitis (UC), and may have a role in animal models of gut fibrosis. We studied the involvement of IL-13 in inflammation and fibrosis in UC and Crohn's disease (CD). Intestinal biopsies and anti-CD3/CD28- or anti-CD2/CD28-stimulated lamina propria mononuclear cells from UC and CD patients and control subjects were cultured, and IL-13, IL-4, IL-5, IL-17A and IFN-γ production was measured. Mucosal IL-13-producing cells were characterised by flow cytometry. Gut explants from strictured CD, non-strictured CD and healthy donors were cultured ex vivo, and secreted IL-13, IL-1ß and collagen were measured. IL-13 production by mucosal explants and activated lamina propria mononuclear cells did not differ between CD, UC and control subjects, and was at least a log lower than IFN-γ and IL-17A. IL-13-producing cells, and in particular natural killer T cells, were uniformly low in all groups. IL-4 and IL-5 were undetectable in culture supernatants. Explants of CD strictures produced low amounts of IL-13, whereas IL-1ß and collagen were elevated. We could not confirm that UC or strictured CD are associated with elevated IL-13 production. These data suggest that an anti-IL-13 Ab would not be an appropriate therapeutic strategy in inflammatory bowel disease.

Thymol-loaded liposomes effectively induced apoptosis and decreased EGFR expression in colorectal cancer cells.

BACKGROUND: Colorectal cancer (CRC) is one of the most common and deadly cancers worldwide. Different factors, such as environmental and genetic factors and lifestyle, affect it. Owing to the presence of phenolic, alkaloid, antioxidant, and terpenoid compounds, herbal compounds can be effective in the treatment of various cancers. Thymol is a natural monoterpene phenol that is abundant in some plants and exerts several biological effects. The aim of this study was to investigate the apoptotic, anti-proliferative effect and EGFR gene expression under the influence of thymol-loaded nanoliposome in SW84 and SW111 cell lines derived from colorectal cancer. MATERIALS AND METHODS: The lipid thin-film hydration method was used to synthesize thymol-loaded liposomes, and their characterization was performed using TEM, DLS, and HPLC analyses. SW84 and SW1111 cells were treated with thymol- and thymol-loaded liposomes at different doses, the inhibition of cell proliferation was evaluated using an MTT assay, the rate of apoptosis induction was assessed using flow cytometry, and EGFR gene expression was measured using real-time PCR. RESULTS: The nanoparticles produced were spherical, uniform, and 200 ± 10 nm in size. HPLC analysis showed that approximately 98% thymol was loaded into the nanoliposome. The results of the MTT assay showed that thymol and thymol-nanoliposomes decreased the proliferation of SW84 and SW1111 cells in a concentration-dependent manner. The IC50 of thymol and thymol-nanoliposomes were 18 and 14.2 µg/ml for the SW48 cell line (P = 0.04) and 10.5 and 6.4 µg/ml for the SW1116 cell line (P = 0.001). Thymol-nanoliposomes significantly inhibited the proliferation of cancer cells compared to free thymol. Flow cytometry showed an increase in the percentage of apoptotic cells, especially in the thymol-nanoliposome group in the treated cells. Real-time PCR results also showed that thymol and thymol-nanoliposome both caused a decrease in the expression of EGFR genes in both cell lines, but this effect of decreasing gene expression was significantly higher in the thymol-nanoliposome group. CONCLUSIONS: Our results showed that thymol-nanoliposomes reduced proliferation, increased apoptosis, and decreased EGFR expression in colorectal cancer-derived cell lines.

Does leucocyte- and platelet-rich fibrin enhance neurosensory recovery after genioplasty? A double-blind, split-mouth, randomised clinical trial.

Neurosensory disturbances (NSD) are common after genioplasty. In this study we aimed to assess the recovery of NSDs with or without leukocyte- and platelet-rich fibrin (L-PRF) following genioplasty. In this double-blind, split-mouth, randomised clinical trial, L-PRF was applied around the mental nerve at the osteotomy site in genioplasty (treatment side). The contralateral side was considered the control side. Two-point discrimination (TPD) test, brush test, and self-reported NSDs (SR-NSD) were used to determine NSD at one, four, and 12 months after genioplasty. Twenty patients were studied. At one and four months after osteotomy, the mean scores of TPD and SR-NSDs were significantly different between the treatment and control sides (p = 0.04, p = 0.01, respectively). The mean of TPD and SR-NSDs was not statistically different on both sides 12 months after operation (p = 0.05, p = 0.71, respectively). The application of L-PRF may enhance the speed of NSD recovery four months after genioplasty.

Pregnenolone enhances the proliferation of mouse neural stem cells and promotes oligodendrogenesis, together with Sox10, and neurogenesis, along with Notch1 and Pax6.

BACKGROUND: Pregnenolone is a precursor of various steroid hormones involved in osteoblast proliferation, microtubules polymerization and cell survival protection. Previous reports focused on the effects of pregnenolone metabolites on stem cell proliferation and differentiation; however, the effects of pregnenolone itself has not been well explored. The present study aimed to investigate the role of pregnenolone on NSC proliferation and to determine the doses required for NSC differentiation as well as the various genes involved in its mechanism of action. METHODS: NSCs were isolated from the embryonic cortex of E14 mice, incubated for 5 days, and then treated with pregnenolone doses of 2, 5, 10, 15 and 20 µM for another 5 days. The number of neurospheres and neurosphere derived cells were then counted. Flow cytometry was used to evaluate the differentiation of NSCs into oligodendrocytes, astrocytes, and neurons. The expression level of Notch1, Pax6 and Sox10 genes were also measured by Real Time PCR after 5 days of treatment. RESULTS: Our data suggest that treatment with 10 µM pregnenolone is optimal for NSC proliferation. In fact, this concentration caused the highest increase in the number of neurospheres and neurosphere derived cells, compared to the control group. In addition, treatment with low doses of pregnenolone (5 and 10 µM) caused a significant increase in NSC differentiation towards immature (Olig2+) and mature (MBP+) oligodendrocyte cell populations, compared to controls. However, NSC differentiation into neurons (beta III tubulin + cells) increased in all treatment groups, with the highest and most significant increase obtained at 15 µM concentration. It is worth noting that pregnenolone at the highest concentration of 15 µM decreased the number of astrocytes (GFAP+). Furthermore, there was an increase of Sox10 expression with low pregnenolone doses, leading to oligodendrogenesis, whereas Notch1 and Pax6 gene expression increased in pregnenolone groups with more neurogenesis. CONCLUSION: Pregnenolone regulates NSCs proliferation in vitro. Treatment with low doses of pregnenolone caused an increase in the differentiation of NSCs into mature oligodendrocytes while higher doses increased the differentiation of NSCs into neurons. Oligodendrogenesis was accompanied by Sox10 while neurogenesis occurred together with Notch1 and Pax6 expression.

Safflower seed oil, a rich source of linoleic acid, stimulates hypothalamic neurogenesis in vivo.

Adult neurogenesis has been reported in the hypothalamus, subventricular zone and subgranular zone in the hippocamp. Recent studies indicated that new cells in the hypothalamus are affected by diet. We previously showed beneficial effects of safflower seed oil (SSO), a rich source of linoleic acid (LA; 74%), on proliferation and differentiation of neural stem cells (NSCs) in vitro. In this study, the effect of SSO on hypothalamic neurogenesis was investigated in vivo, in comparison to synthetic LA. Adult mice were treated with SSO (400 mg/kg) and pure synthetic LA (300 mg/kg), at similar concentrations of LA, for 8 weeks and then hypothalamic NSCs were cultured and subsequently used for Neurosphere-forming assay. In addition, serum levels of brain-derived neurotrophic factor (BNDF) were measured using enzyme-linked immunosorbent assay. Administration of SSO for 8 weeks in adult mice promoted the proliferation of NSCs isolated from SSO-treated mice. Immunofluorescence staining of the hypothalamus showed that the frequency of astrocytes (glial fibrillary acidic protein+ cells) are not affected by LA or SSO. However, the frequency of immature (doublecortin+ cells) and mature (neuronal nuclei+ cells) neurons significantly increased in LA- and SSO-treated mice, compared to vehicle. Furthermore, both LA and SSO caused a significant increase in the serum levels of BDNF. Importantly, SSO acted more potently than LA in all experiments. The presence of other fatty acids in SSO, such as oleic acid and palmitic acid, suggests that they could be responsible for SSO positive effect on hypothalamic proliferation and neurogenesis, compared to synthetic LA at similar concentrations.

Association between neutrophil/lymphocyte ratio and disease severity in scleroderma patients.

Introduction: Systemic sclerosis is a chronic and progressive connective tissue disease with various manifestation. Inflammatory status is developed in early stages and is followed by major organs' dysfunction. Disease severity is evaluated mostly through Medsger scale. There is not any single laboratory test to evaluate disease severity, although some hematologic can reflect disease severity. In this study, we evaluated the association between hematologic indices (specially Neutrophil/Lymphocyte ratio) and Medsger score of disease severity. Materials and methods: One hundred and twenty-three patients along with the same number of healthy controls were enrolled in this study. Demographic information and past medical records were gathered in first appointment. Hematologic indices were calculated based on the laboratory findings and the association between these indices and Medsger score of disease severity was evaluated. Results: One hundred and twenty-three patients with mean disease duration of 9.54 and mean Medsger score of 7.42 were investigated in this study. Neutrophil count, erythrocyte sedimentation rate, red cell distribution width and NLR were significantly higher and mean platelets volume was significantly lower in SSc patients in comparison to controls. NLR was significantly correlated with pulmonary and cardiac involvements and Monocyte/Lymphocyte ratio was significantly correlated with the involvement of joint and tendons. We showed that NLR is a predictive factor for the severity of systemic sclerosis. We also found a cut off Value of 1.9 for NLR as a predictor for disease severity in our patients. Conclusion: Our study shows that SSc and its severity is associated with some hematologic indices like NLR, MLR, platelets and hemoglobin. These indices can also specifically predict the involvement of some organs.

Predictors of rural driver self-reported passing behaviors when interacting with farm equipment on the roadway.

Background: Crashes involving farm equipment (FE) are a major safety concern for farmers as well as all other users of the public road system in both rural and urban areas. These crashes often involve passenger vehicle drivers striking the farm equipment from behind or attempting to pass, but little is known about drivers' perceived norms and self-reported passing behaviors. The objective of this study is to examine factors influencing drivers' farm equipment passing frequencies and their perceptions about the passing behaviors of other drivers. Methods: Data were collected via intercept surveys with adult drivers at local gas stations in two small rural towns in Iowa. The survey asked drivers about their demographic information, frequency of passing farm equipment, and perceptions of other drivers' passing behavior in their community and state when approaching farm equipment (proximal and distal descriptive norms). A multinomial logistic regression model was used to estimate the relationship between descriptive norms and self-reported passing behavior. Results: Survey data from 201 adult drivers showed that only 10% of respondents considered farm equipment crashes to be a top road safety concern. Respondents who perceived others passing farm equipment frequently in their community were more likely to report that they also frequently pass farm equipment. The results also showed interactions between gender and experience operating farm equipment in terms of self-reported passing behavior. Conclusions/Implications: Results from this study suggest local and state-level norms and perceptions of those norms may be important targets for intervention to improve individual driving behaviors around farm equipment.

Melatonin ameliorates disease severity in a mouse model of multiple sclerosis by modulating the kynurenine pathway.

Melatonin (MT), a neurohormone with immunomodulatory properties, is one of the metabolites produced in the brain from tryptophan (TRP) that has already strong links with the neuropathogenesis of Multiple sclerosis (MS). However, the exact molecular mechanisms behind that are not fully understood. There is some evidence showing that MS and MT are interconnected via different pathways: Relapses of MS has a direct correlation with a low level of MT secretion and a growing body of evidence suggest that MT be therapeutic in Experimental Autoimmune Encephalomyelitis (EAE, a recognise animal model of MS) severity. Previous studies have demonstrated that the kynurenine pathway (KP), the main pathway of TRP catabolism, plays a key role in the pathogenesis of MS in humans and in EAE. The present study aimed to investigate whether MT can improve clinical signs in the EAE model by modulating the KP. C57BL/6 mice were induced with EAE and received different doses of MT. Then the onset and severity of EAE clinical symptoms were recorded. Two biological factors, aryl hydrocarbon receptor (AhR) and NAD+ which closely interact in the KP were also assessed. The results indicated that MT treatment at all tested doses significantly decrease the EAE clinical scores and the number of demyelinating plaques. Furthermore, MT treatment reduced the mRNA expression of the KP regulatory enzyme indoleamine 2,3-dioxygenase 1(IDO-1) and other KP enzymes. We also found that MT treatment reduces the mRNA expression of the AhR and inhibits the enzyme Nicotinamide N-Methyltransferase (Nnmt) overexpression leading to an increase in NAD+ levels. Collectively, this study suggests that MT treatment may significantly attenuates the severity of EAE by altering the KP, AhR and NAD+ metabolism.

Evaluation of the Biodistribution of Arginine, glycine, aspartic acid peptide-modified Nanoliposomes Containing Curcumin in Rats.

Background: Liposomes, as a biological membrane, is successfully used for drug delivery, reduces toxicity in normal cells and improves bio-accessibility of the drug to the target cells. Curcumin, as a bioactive substance with pleiotropic biological activities, is an anti-inflammatory compound and has several anticancer effects in different cancers such as pancreatic and breast cancer. Objectives: This study was conducted to determine the bio-distribution of arginine-glycine-aspartic acid (RGD)-modified nanoliposomes containing curcumin in different tissues of rats. Materials and Methods: The amount of curcumin in each tissue was examined by HPLC analysis. The distribution of liposomal Hoechst in the rats was evaluated by using fluorescence spectrophotometry, live animal imaging analyses and histological methods. Results: HPLC analysis showed the mean of curcumin in the blood significantly increased in the liposomal curcumin modified with RGD compared to free curcumin. These results were confirmed by fluorescence measurement for RGD modified liposome containing Hoechst dye. There was negligible fluorescent intensity in the blood rats, which received Hoechst alone. Live animal imaging analysis showed the presence of fluorescent color in heart tissue for all groups. It was also detected in kidney tissue for liposomal Hoechst modified with RGD group. Conclusions: The present study demonstrated that RGD-modified nano-liposomes can significantly improve drug retention time in the blood of rats.

Hormones in experimental autoimmune encephalomyelitis (EAE) animal models.

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) in which activated immune cells attack the CNS and cause inflammation and demyelination. While the etiology of MS is still largely unknown, the interaction between hormones and the immune system plays a role in disease progression, but the mechanisms by which this occurs are incompletely understood. Several in vitro and in vivo experimental, but also clinical studies, have addressed the possible role of the endocrine system in susceptibility and severity of autoimmune diseases. Although there are several demyelinating models, experimental autoimmune encephalomyelitis (EAE) is the oldest and most commonly used model for MS in laboratory animals which enables researchers to translate their findings from EAE into human. Evidences imply that there is great heterogeneity in the susceptibility to the induction, the method of induction, and the response to various immunological or pharmacological interventions, which led to conflicting results on the role of specific hormones in the EAE model. In this review, we address the role of endocrine system in EAE model to provide a comprehensive view and a better understanding of the interactions between the endocrine and the immune systems in various models of EAE, to open up a ground for further detailed studies in this field by considering and comparing the results and models used in previous studies.

17ß-Estradiol Reduces Demyelination in Cuprizone-fed Mice by Promoting M2 Microglia Polarity and Regulating NLRP3 Inflammasome.

Estrogen produces a beneficial role in animal models of multiple sclerosis (MS). The effect of 17ß-estradiol therapy on microglia polarization and neuroinflammation in the corpus callosum of the cuprizone-induced demyelination model has not been elucidated. In this study, mice were given 0.2% cuprizone (CPZ) for 5 weeks to induce demyelination during which they received 50 ng of 17ß-estradiol (EST), injected subcutaneously in the neck region, twice weekly. Data revealed that treatment with 17ß-estradiol therapy (CPZ+EST) improved neurological behavioral deficits, displayed by a significant reduction in escape latencies, in comparison to untreated CPZ mice. Also, administration of 17ß-estradiol caused a decrease in demyelination levels and axonal injury, as demonstrated by staining with Luxol fast blue, immunofluorescence to myelin basic protein, and transmission electron microscopy analysis. In addition, at the transcriptional level in the brain, mice treated with 17ß-estradiol (CPZ+EST) showed a decrease in the levels of M1-assosicted microglia markers (CD86, iNOS and MHC-II) whereas M2-associated genes (Arg-1, CD206 and Trem-2) were increased, compared to CPZ mice. Moreover, administration of 17ß-estradiol resulted in a significant reduction (∼3-fold) in transcript levels of NLRP3 inflammasome and its downstream product IL-18, compared to controls. In summary, this study demonstrated for the first time that exogenous 17ß-estradiol therapy robustly leads to the reduction of M1 phenotype, stimulation of polarized M2 microglia, and repression of NLRP3 inflammasome in the corpus callosum of CPZ demyelination model of MS. The positive effects of 17ß-estradiol on microglia and inflammasome seems to facilitate and accelerate the remyelination process.

Feasibility and safety of endoscopic full-thickness esophageal wall resection and defect closure: a prospective long-term survival animal study.

BACKGROUND: The first experiences with endoscopic closure of esophageal perforations in animal survival studies encouraged us to extend these procedures to full-thickness resections of pieces of the esophageal wall (FTEW). OBJECTIVE: To learn the feasibility, safety, and long-term effects of FTEW removal and defect closure. DESIGN: Feasibility animal study. SETTING: Approved animal facility. INTERVENTIONS: Twelve pigs were used for 3-month survival studies, autopsy, and histologic examination. Resection of a 2-cm piece of wall was performed with needle-knife and forceps/snare. Closure was performed by using prototype endoscopic suturing. MAIN OUTCOME MEASUREMENTS: Feasibility and complication assessment of this new endoscopic method. RESULTS: There were no complications relating to incision, resection, or closure. All pigs recovered quickly. In 2 animals a larger piece of wall causing a larger defect was removed, resulting in much air penetrating into the mediastinum, causing difficult ventilation. This was resolved with thoracic drain. In 3 of 12 animals a toxic substance slipped into the mediastinum, resulting in an abscess in 1 pig and misfire of an anchor as a result of obscured vision. This caused temporary illness of the animal but not death. Autopsy and histologic study confirmed no mediastinitis and well-healed scars in all but one. LIMITATION: Animal study. CONCLUSION: FTEW has proven to be feasible. Long-term survival demonstrated no mediastinitis and only 1 abscess after contamination of the mediastinum. These first experiences encourage further animal studies because the prospect of endoscopic full-thickness removal of esophageal lesions in patients might be very advantageous.

GLI inhibitors overcome Erlotinib resistance in human pancreatic cancer cells by modulating E-cadherin.

Inhibition of hedgehog (Hh) signalling pathway, including its end effector GLI1, can reverse epithelial-to-mesenchymal transition (EMT) which plays an important role in drug resistance of pancreatic cancer cells to Erlotinib (ETB). This study investigated the effect of GLI inhibitors Forskolin (FSK), GANT-61 (GNT), and Arsenic trioxide (ATX) on suppressing the resistance of pancreatic cancer cells to ETB. The effect of GLI inhibitors was evaluated by measuring mRNA expression levels of EMT factors using quantitative RT-PCR. Immunocytochemistry and flow cytometry were used to assess E-cadherin (E-Cad) and GLI1 protein levels. MTT and apoptosis assays were used to evaluate the synergistic effects for the combination treatment of each GLI inhibitor with ETB. Pancreatic cancer cells PANC-1 treated by GNT showed the highest significant reduction in mRNA levels of GLI1 and other EMT pathway genes. Moreover, GNT was able to upregulate E-Cad and downregulate GLI1 proteins, more than FSK, while ATX had no effect. Apoptosis levels of PANC-1 cells following treatment with LD30 concentrations of FSK, GNT, or ATX, showed 57%, 62% and 67%, respectively, in comparison to ETB (∼48%). Importantly, combination treatments of ETB with either FSK, GNT, or ATX demonstrated a significant increase in apoptotic cells reaching 61% (ETB + FSK), 80% (ETB + GNT) or 88% (ETB + ATX). FSK did not have much effect on the drug resistance of PANC-1 cells to ETB. However, GNT, but more effectively ATX, were able to reduce the drug resistance of this cell line to ETB.

Melatonin Therapy Modulates Cerebral Metabolism and Enhances Remyelination by Increasing PDK4 in a Mouse Model of Multiple Sclerosis.

Metabolic disturbances have been implicated in demyelinating diseases including multiple sclerosis (MS). Melatonin, a naturally occurring hormone, has emerged as a potent neuroprotective candidate to reduce myelin loss and improve MS outcomes. In this study, we evaluated the effect of melatonin, at both physiological and pharmacological doses, on oligodendrocytes metabolism in an experimental autoimmune encephalomyelitis (EAE) mouse model of MS. Results showed that melatonin decreased neurological disability scores and enhanced remyelination, significantly increasing myelin protein levels including MBP, MOG, and MOBP. In addition, melatonin attenuated inflammation by reducing pro-inflammatory cytokines (IL-1ß and TNF-α) and increasing anti-inflammatory cytokines (IL-4 and IL-10). Moreover, melatonin significantly increased brain concentrations of lactate, N-acetylaspartate (NAA), and 3-hydroxy-3-methylglutaryl-coenzyme-A reductase (HMGCR). Pyruvate dehydrogenase kinase-4 (PDK-4) mRNA and protein expression levels were also increased in melatonin-treated, compared to untreated EAE mice. However, melatonin significantly inhibited active and total pyruvate dehydrogenase complex (PDC), an enzyme under the control of PDK4. In summary, although PDC activity was reduced by melatonin, it caused a reduction in inflammatory mediators while stimulating oligodendrogenesis, suggesting that oligodendrocytes are forced to use an alternative pathway to synthesize fatty acids for remyelination. We propose that combining melatonin and PDK inhibitors may provide greater benefits for MS patients than the use of melatonin therapy alone.