Cell-based gene therapy for mending infarcted hearts

The goal of this study was to analyse the efficiency of a combinatorial cell/growth factor therapy to improve function of infarcted murine hearts. The Insulin-like Growth Factor-1 (IGF-1) isoform, IGF-1Ea, has been shown to reduce scar formation and decrease cell death after MI. The present study utilized P19Cl6-derived, IGF-1Ea over-expressing cardiomyocytes to achieve its goal. The P19Cl6 cells were stably transduced with IGF-1Ea using a lentiviral vector and investigated first in vitro for their feasibility for in vivo cell therapy. The engineered pluripotent cells over-expressing IGF-1Ea survived better to hypoxia-induced injury than the control cells. The cells maintained their pluripotency and efficient differentiation capacity towards ventricular cardiomyocyte lineage, generating large quantities of cardiomyocytes optimal for the transplantation study. The generated cardiomyocytes were functionally active and exhibited a mature phenotype. Transplantation of the cardiomyocytes into allogeneic wild type murine infarcted hearts conferred a tendency for maintenance of function at short-term time point. At long-term however, this effect was lost, returning to the level of the control infarcted hearts. Cell tracing assessment revealed engraftment of both IGF-1Ea- and empty-cells, although the cells failed to couple with the recipient tissue. Scar size and capillary density analyses revealed no significant difference between the cells transplanted compared to the saline treated hearts, corroborating with the long-term functional data. Interestingly, the IGF- 1Ea-cell transplanted hearts expressed significantly higher amount of VEGFa compared to the controls, albeit no change in capillary density. Further investigation revealed that the enhanced VEGFa expression in IGF-1Ea-cells transplanted hearts was associated with reduced hypertrophy, marked by reduced cell cross-sectional area at the border-zone, aSK and bMHC expression compared to the control hearts. Nonetheless, modulation of hypertrophic response and transplantation of IGF-1Ea-cells were not able to confer lasting functional preservation, possibly due to lack of sufficient engraftment and coupling of the transplanted cells

Increased cardiogenesis in P19-GFP teratocarcinoma cells expressing the propeptide IGF-1Ea

AbstractThe mechanism implicated in differentiation of endogenous cardiac stem cells into cardiomyocytes to regenerate the heart tissue upon an insult remains elusive, limiting the therapeutical goals to exogenous cell injection and/or gene therapy. We have shown previously that cardiac specific overexpression of the insulin-like growth factor 1 propeptide IGF-1Ea induces beneficial myocardial repair after infarct. Although the mechanism is still under investigation, the possibility that this propeptide may be involved in promoting stem cell differentiation into the cardiac lineage has yet to be explored. To investigate whether IGF-1Ea promote cardiogenesis, we initially modified P19 embryonal carcinoma cells to express IGF-1Ea. Taking advantage of their cardiomyogenic nature, we analyzed whether overexpression of this propeptide affected cardiac differentiation program. The data herein presented showed for the first time that constitutively overexpressed IGF-1Ea increased cardiogenic differentiation program in both undifferentiated and DMSO-differentiated cells. In details, IGF-1Ea overexpression promoted localization of alpha-actinin in finely organized sarcomeric structure compared to control cells and upregulated the cardiac mesodermal marker NKX-2.5 and the ventricular structural protein MLC2v. Furthermore, activated IGF-1 signaling promoted cardiac mesodermal induction in undifferentiated cells independently of cell proliferation. This analysis suggests that IGF-1Ea may be a good candidate to improve both in vitro production of cardiomyocytes from pluripotent stem cells and in vivo activation of the differentiation program of cardiac progenitor cells

Cell-based gene therapy for mending infarcted hearts

The goal of this study was to analyse the efficiency of a combinatorial cell/growth factor therapy to improve function of infarcted murine hearts. The Insulin-like Growth Factor-1 (IGF-1) isoform, IGF-1Ea, has been shown to reduce scar formation and decrease cell death after MI. The present study utilized P19Cl6-derived, IGF-1Ea over-expressing cardiomyocytes to achieve its goal. The P19Cl6 cells were stably transduced with IGF-1Ea using a lentiviral vector and investigated first in vitro for their feasibility for in vivo cell therapy. The engineered pluripotent cells over-expressing IGF-1Ea survived better to hypoxia-induced injury than the control cells. The cells maintained their pluripotency and efficient differentiation capacity towards ventricular cardiomyocyte lineage, generating large quantities of cardiomyocytes optimal for the transplantation study. The generated cardiomyocytes were functionally active and exhibited a mature phenotype. Transplantation of the cardiomyocytes into allogeneic wild type murine infarcted hearts conferred a tendency for maintenance of function at short-term time point. At long-term however, this effect was lost, returning to the level of the control infarcted hearts. Cell tracing assessment revealed engraftment of both IGF-1Ea- and empty-cells, although the cells failed to couple with the recipient tissue. Scar size and capillary density analyses revealed no significant difference between the cells transplanted compared to the saline treated hearts, corroborating with the long-term functional data. Interestingly, the IGF- 1Ea-cell transplanted hearts expressed significantly higher amount of VEGFa compared to the controls, albeit no change in capillary density. Further investigation revealed that the enhanced VEGFa expression in IGF-1Ea-cells transplanted hearts was associated with reduced hypertrophy, marked by reduced cell cross-sectional area at the border-zone, aSK and bMHC expression compared to the control hearts. Nonetheless, modulation of hypertrophic response and transplantation of IGF-1Ea-cells were not able to confer lasting functional preservation, possibly due to lack of sufficient engraftment and coupling of the transplanted cells.EThOS - Electronic Theses Online ServiceEMBOGBUnited Kingdo

Prevalence and factors associated with depression, anxiety and stress symptoms among construction workers in Nepal.

IntroductionThe construction industry in Nepal, which employs a significant proportion of the population, ranks as one of the largest industries in the country. Construction work is physically demanding and can be risky due to the use of heavy machinery and the presence of intense physical labor. However, the physical and mental health of construction workers in Nepal is often neglected. This study aimed to assess psychological distress (depression, anxiety, and stress symptoms) and its association with socio-demographic, lifestyle, and occupational factors among construction workers in Kavre district, Nepal.MethodsWe conducted a cross-sectional study from 1st October 2019 to 15th January 2020 among 402 construction workers in Banepa, and Panauti municipalities of Kavre district, Nepal. We collected data with face-to-face interviews using a structured questionnaire consisting of a) socio-demographic characteristics; b) lifestyle and occupational characteristics; and c) depression, anxiety and stress symptoms. We collected data using electronic forms in KoboToolbox and imported them into R version 3.6.2 for statistical analysis. We present parametric numerical variables as mean and standard deviation, and categorical variables as percentage and frequency. The confidence interval around proportion was estimated with the Clopper-Pearson method. We applied univariate and multivariable logistic regression to determine factors associated with depression symptoms, anxiety, and stress. The result of logistic regression was presented as crude odds ratio, adjusted odds ratio (AOR), and their 95% confidence interval (CI).ResultsThe prevalence of depression, anxiety and stress symptoms were 17.1% (95%CI: 13.6-21.2), 19.2% (95%CI: 15.5-23.4) and 16.4% (95%CI: 12.9-20.4), respectively. In multivariable logistic regression analysis, depression symptom was positively associated with poor sleep quality (AOR = 3.51; 95%CI: 1.5-8.19; p-value: 0.004); stress symptom was positively associated with Brahmin ethnicity (AOR = 3.76; 95%CI:1.34-10.58; p-value: 0.012) and current smoking (AOR = 2.0; 95%CI: 1.11-3.82 p-value: 0.022). But anxiety symptoms were not associated with any of the variables.ConclusionsThe prevalence of depression, anxiety, and stress symptoms were high among construction workers. Developing evidence-based and appropriate community-based mental health prevention programs among laborers and construction workers is recommended

Estimation of Total Quercetin and Rutin Content in Malus domestica of Nepalese Origin by HPLC Method and Determination of Their Antioxidative Activity

Malus domestica (Apple) is one of the most widely cultivated cash crops of Nepal. Jumla and Mustang are two major pocket areas for the production of apple. Flavonoids including quercetin and rutin are potent antioxidants present in apples. This study was designed to quantify and compare the presence of quercetin and rutin in different plant parts (peel, leaf, and bark) among various cultivars of Malus domestica from two pocket zones of Nepal. A new HPLC-UV method was developed and validated for the quantification of quercetin and rutin. Polyphenols, flavonoids, and carbohydrate contents were determined by colorimetric methods. 2,2′-Diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging assay was carried out to measure in vitro antioxidative activity. Acid hydrolysis of each extract was carried out by the standard method to measure aglycone quercetin content after hydrolysis of its glycosides. The total rutin content ranged from 3.69 ± 1.34 to 374.50 ± 2.35 mg/100g dry extract weight. Before the acidic hydrolysis, the total quercetin content ranged from 2.96 ± 0.13 to 171.05 ± 0.95 mg/100g dry extract weight whereas its amount increased highly after the hydrolysis and it ranged from 80.84 ± 19.65 to 7445.32 ± 29.25 mg/100g dry extract weight. Total polyphenol content ranged from 19.48 ± 0.23 to 123.48 ± 1.84 µg gallic acid equivalent/mg of dry extract weight. Similarly, flavonoid content ranged from 2.21 ± 0.72 µg to 755.54 ± 1.91 µg quercetin equivalent/mg of dry extract weight. Total carbohydrate content ranged from 144.15 ± 3.73 to 484.65 ± 2.63 µg glucose equivalent per 0.5 mg dry extract weight. All the extracts showed the various degrees of antioxidant activity in a dose-dependent manner. Among them, stem bark of the Jonathan Jumla showed potent antioxidant activity with IC50 value of 13.003 µg/mL. The present study provides the information about variation of the phytochemical content among the different cultivars, parts, and geographic locations. Furthermore, it revealed that bark of Malus domestica cultivars had high quercetin and rutin content with high antioxidant activity