Gene therapy is being considered as a treatment/cure for type 1 diabetes (T1D). Previously we use... more Gene therapy is being considered as a treatment/cure for type 1 diabetes (T1D). Previously we used a clinically-applicable AAV to deliver furin cleavable insulin (INS-FUR) to the livers of diabetic non-obese diabetic mice. The traditional AAV8 that allows predominantly episomal expression, and the hybrid AAV8/piggyBac that results in transgene integration into the host genome were used. Euglycaemia was achieved in mice (n=4) that received AAV8/piggyBac-INS-FUR, but not in mice that received AAV8-INS-FUR. In the current study global transcriptomic profiling was carried out, by total RNA sequencing, to compare the key pathways modulated in hepatocytes that reversed diabetes with those that did not. Using Qiagen CLC Workbench, significant genes were identified based on fold change expression cut offs of, and a false discovery rate p-value of <0.05. Selected genes were mapped onto the various cellular pathways using Qiagen Ingenuity Pathway Analysis (IPA) software to determine trends...
Background: The sphingosine kinase 1 (SphK1) isoenzyme synthesises sphingosine-1-phosphate (S1P) ... more Background: The sphingosine kinase 1 (SphK1) isoenzyme synthesises sphingosine-1-phosphate (S1P) 1 and plays a critical role in gut-liver diseases such as fatty liver, inflammatory bowel diseases and colon cancers. SphK1 is expressed as two major isoforms, SphK1a and SphK1b, both presenting common and distinct interacting functions depending on tissue type and location within the cell. Here, in this report, we examined the expression of SphK1 isoforms in normal and cancer human liver tissues and compare the isoform expression with different cells and tissue types and explore its relevance to the diagnosis and treatment of liver cancer. The overall aim of the study was to determine the SphK1 isoform status and importance in the liver and liver cancer. Methods: Polymerase chain reaction (PCR) primers were designed overlapping the SphK1a-b region and within the SphK1a region to differentiate the two isoforms. Qualitative RTPCR was used to determine the status of the SphK1a and SphK1b expression in normal and cancer cells lines, and in human tissue samples from patients with liver cancer (hepatocellular carcinoma). Results: Overall SphK1a is the most dominant isoform expressed in most tissue types whereas SphK1b is cell and tissue type specific. In cancer and adjacent liver tissue strong expression of SphK1a is detected, while SphK1b is not detected in the same samples and cell lines. Conclusion: Our data suggest that overall SphK1a is the predominant isoform in most cell lines and human tissues whilst SphK1b is cell and tissue type specific. In cells associated with the gut-liver axis only SphK1a is detected suggesting that SphK1a expression is important for normal gut-liver function, whereby the lack of SphK1b expression indicates that this isoform function may be redundant in this tissue. Although we see no observable change in SphK1a expression in cancer and adjacent liver tissues its strong expression may still influence disease outcome given that knocking out SphK1 offered protection from liver accumulation and inflammation in a mouse model
Context There is substantial evidence that reduced short-chain fatty acids (SCFAs) in the gut are... more Context There is substantial evidence that reduced short-chain fatty acids (SCFAs) in the gut are associated with obesity and type 2 diabetes, although findings from clinical interventions that can increase SCFAs are inconsistent. Objective This systematic review and meta-analysis aimed to assess the effect of SCFA interventions on fasting glucose, fasting insulin, and homeostatic model assessment of insulin resistance (HOMA-IR). Data Sources Relevant articles published up to July 28, 2022, were extracted from PubMed and Embase using the MeSH (Medical Subject Headings) terms of the defined keywords [(short-chain fatty acids) AND (obesity OR diabetes OR insulin sensitivity)] and their synonyms. Data analyses were performed independently by two researchers who used the Cochrane meta-analysis checklist and the PRISMA guidelines. Data Extraction Clinical studies and trials that measured SCFAs and reported glucose homeostasis parameters were included in the analysis. Standardized mean differences (SMDs) with 95%CIs were calculated using a random-effects model in the data extraction tool Review Manager version 5.4 (RevMan 5.4). The risk-of-bias assessment was performed following the Cochrane checklist for randomized and crossover studies. Data Analysis In total, 6040 nonduplicate studies were identified, 23 of which met the defined criteria, reported fasting insulin, fasting glucose, or HOMA-IR values, and reported change in SCFA concentrations post intervention. Meta-analyses of these studies indicated that fasting insulin concentrations were significantly reduced (overall effect: SMD = −0.15; 95%CI = −0.29 to −0.01, P = 0.04) in treatment groups, relative to placebo groups, at the end of the intervention. Studies with a confirmed increase in SCFAs at the end of intervention also had a significant effect on lowering fasting insulin (P = 0.008). Elevated levels of SCFAs, compared with baseline levels, were associated with beneficial effects on HOMA-IR (P &lt; 0.00001). There was no significant change in fasting glucose concentrations. Conclusion Increased postintervention levels of SCFAs are associated with lower fasting insulin concentrations, offering a beneficial effect on insulin sensitivity. Systematic Review Registration PROSPERO registration number CRD42021257248.
ABSTRACT Abstract This pilot study has shown that dPCR possesses sufficient sensitivity and speci... more ABSTRACT Abstract This pilot study has shown that dPCR possesses sufficient sensitivity and specificity for the detection of MRD in MM patients in remission, even in PB samples.
Type 1 Diabetes (T1D) is a chronic metabolic disorder for which current treatments are unable to ... more Type 1 Diabetes (T1D) is a chronic metabolic disorder for which current treatments are unable to prevent the onset of complications. Previously, we used an adeno-associated viral vector (AAV8) to deliver furin-cleavable human insulin (INS-FUR) to the livers of diabetic non-obese diabetic (NOD) mice to reverse T1D. The use of the traditional AAV8-INS-FUR vector could not bring about normoglycemia. However, this vector, coupled with a transposon system in the AAV8/piggyBac-INS-FUR vector, was able to do so. This study aimed to investigate the transcriptomic profiles of the livers of diabetic, AAV8-INS-FUR-transduced, and AAV8/piggyBac-INS-FUR-transduced NOD mice and compare these to the normal liver to identify genetic differences resulting from delivery of the AAV8/piggyBac-INS-FUR vector which produced normoglycemia. Differential gene expression was determined by RNA-Seq analysis and differentially expressed genes from each treatment were mapped onto cellular pathways to determine t...
Gene therapy is being considered as a treatment/cure for type 1 diabetes (T1D). Previously we use... more Gene therapy is being considered as a treatment/cure for type 1 diabetes (T1D). Previously we used a clinically-applicable AAV to deliver furin cleavable insulin (INS-FUR) to the livers of diabetic non-obese diabetic mice. The traditional AAV8 that allows predominantly episomal expression, and the hybrid AAV8/piggyBac that results in transgene integration into the host genome were used. Euglycaemia was achieved in mice (n=4) that received AAV8/piggyBac-INS-FUR, but not in mice that received AAV8-INS-FUR. In the current study global transcriptomic profiling was carried out, by total RNA sequencing, to compare the key pathways modulated in hepatocytes that reversed diabetes with those that did not. Using Qiagen CLC Workbench, significant genes were identified based on fold change expression cut offs of, and a false discovery rate p-value of <0.05. Selected genes were mapped onto the various cellular pathways using Qiagen Ingenuity Pathway Analysis (IPA) software to determine trends...
Background: The sphingosine kinase 1 (SphK1) isoenzyme synthesises sphingosine-1-phosphate (S1P) ... more Background: The sphingosine kinase 1 (SphK1) isoenzyme synthesises sphingosine-1-phosphate (S1P) 1 and plays a critical role in gut-liver diseases such as fatty liver, inflammatory bowel diseases and colon cancers. SphK1 is expressed as two major isoforms, SphK1a and SphK1b, both presenting common and distinct interacting functions depending on tissue type and location within the cell. Here, in this report, we examined the expression of SphK1 isoforms in normal and cancer human liver tissues and compare the isoform expression with different cells and tissue types and explore its relevance to the diagnosis and treatment of liver cancer. The overall aim of the study was to determine the SphK1 isoform status and importance in the liver and liver cancer. Methods: Polymerase chain reaction (PCR) primers were designed overlapping the SphK1a-b region and within the SphK1a region to differentiate the two isoforms. Qualitative RTPCR was used to determine the status of the SphK1a and SphK1b expression in normal and cancer cells lines, and in human tissue samples from patients with liver cancer (hepatocellular carcinoma). Results: Overall SphK1a is the most dominant isoform expressed in most tissue types whereas SphK1b is cell and tissue type specific. In cancer and adjacent liver tissue strong expression of SphK1a is detected, while SphK1b is not detected in the same samples and cell lines. Conclusion: Our data suggest that overall SphK1a is the predominant isoform in most cell lines and human tissues whilst SphK1b is cell and tissue type specific. In cells associated with the gut-liver axis only SphK1a is detected suggesting that SphK1a expression is important for normal gut-liver function, whereby the lack of SphK1b expression indicates that this isoform function may be redundant in this tissue. Although we see no observable change in SphK1a expression in cancer and adjacent liver tissues its strong expression may still influence disease outcome given that knocking out SphK1 offered protection from liver accumulation and inflammation in a mouse model
Context There is substantial evidence that reduced short-chain fatty acids (SCFAs) in the gut are... more Context There is substantial evidence that reduced short-chain fatty acids (SCFAs) in the gut are associated with obesity and type 2 diabetes, although findings from clinical interventions that can increase SCFAs are inconsistent. Objective This systematic review and meta-analysis aimed to assess the effect of SCFA interventions on fasting glucose, fasting insulin, and homeostatic model assessment of insulin resistance (HOMA-IR). Data Sources Relevant articles published up to July 28, 2022, were extracted from PubMed and Embase using the MeSH (Medical Subject Headings) terms of the defined keywords [(short-chain fatty acids) AND (obesity OR diabetes OR insulin sensitivity)] and their synonyms. Data analyses were performed independently by two researchers who used the Cochrane meta-analysis checklist and the PRISMA guidelines. Data Extraction Clinical studies and trials that measured SCFAs and reported glucose homeostasis parameters were included in the analysis. Standardized mean differences (SMDs) with 95%CIs were calculated using a random-effects model in the data extraction tool Review Manager version 5.4 (RevMan 5.4). The risk-of-bias assessment was performed following the Cochrane checklist for randomized and crossover studies. Data Analysis In total, 6040 nonduplicate studies were identified, 23 of which met the defined criteria, reported fasting insulin, fasting glucose, or HOMA-IR values, and reported change in SCFA concentrations post intervention. Meta-analyses of these studies indicated that fasting insulin concentrations were significantly reduced (overall effect: SMD = −0.15; 95%CI = −0.29 to −0.01, P = 0.04) in treatment groups, relative to placebo groups, at the end of the intervention. Studies with a confirmed increase in SCFAs at the end of intervention also had a significant effect on lowering fasting insulin (P = 0.008). Elevated levels of SCFAs, compared with baseline levels, were associated with beneficial effects on HOMA-IR (P &lt; 0.00001). There was no significant change in fasting glucose concentrations. Conclusion Increased postintervention levels of SCFAs are associated with lower fasting insulin concentrations, offering a beneficial effect on insulin sensitivity. Systematic Review Registration PROSPERO registration number CRD42021257248.
ABSTRACT Abstract This pilot study has shown that dPCR possesses sufficient sensitivity and speci... more ABSTRACT Abstract This pilot study has shown that dPCR possesses sufficient sensitivity and specificity for the detection of MRD in MM patients in remission, even in PB samples.
Type 1 Diabetes (T1D) is a chronic metabolic disorder for which current treatments are unable to ... more Type 1 Diabetes (T1D) is a chronic metabolic disorder for which current treatments are unable to prevent the onset of complications. Previously, we used an adeno-associated viral vector (AAV8) to deliver furin-cleavable human insulin (INS-FUR) to the livers of diabetic non-obese diabetic (NOD) mice to reverse T1D. The use of the traditional AAV8-INS-FUR vector could not bring about normoglycemia. However, this vector, coupled with a transposon system in the AAV8/piggyBac-INS-FUR vector, was able to do so. This study aimed to investigate the transcriptomic profiles of the livers of diabetic, AAV8-INS-FUR-transduced, and AAV8/piggyBac-INS-FUR-transduced NOD mice and compare these to the normal liver to identify genetic differences resulting from delivery of the AAV8/piggyBac-INS-FUR vector which produced normoglycemia. Differential gene expression was determined by RNA-Seq analysis and differentially expressed genes from each treatment were mapped onto cellular pathways to determine t...
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Papers by Najah T Nassif