samina akbar - Academia.edu (original) (raw)
Papers by samina akbar
International Journal of Molecular Sciences
Garcinia cambogia extract (GCE) is a popular weight-loss supplement that also lowers plasma trigl... more Garcinia cambogia extract (GCE) is a popular weight-loss supplement that also lowers plasma triglyceride (TG) levels. We hypothesized that GCE-mediated inhibition of ATP citrate lyase and thereby hepatic TG production could lead to compensatory mechanisms, including increased hepatic TG uptake via lipoprotein receptors. GCE (20 mg/day) administered 40 days orally to female C57BL/6Rj mice on a standard chow diet led to a decrease in both plasma fasting and post-prandial TG-rich lipoprotein levels, but with no significant change in body weight gain. Lipolysis stimulated lipoprotein receptor (LSR) protein levels, but not those of LDL-receptor, were increased as compared to controls. Mouse Hepa1-6 cells treated with the GCE active ingredient, hydroxycitrate, also led to increased LSR protein levels. Hepatic total cholesterol, TG, and muscle TG contents were higher in GCE-treated animals as compared to controls, whereas adipose TG levels were unchanged. LSR and LDL-receptor protein level...
The FASEB Journal, 2015
Elevated postprandial lipemia (PPL) as an important risk factor for cardiovascular disease has be... more Elevated postprandial lipemia (PPL) as an important risk factor for cardiovascular disease has been attributed to the accumulation of atherogenic remnant lipoproteins in the circulation. The hepati...
Neurobiology of aging, Jan 3, 2018
The ε4 allele of the apolipoprotein E (APOE) gene common polymorphism is the strongest genetic ri... more The ε4 allele of the apolipoprotein E (APOE) gene common polymorphism is the strongest genetic risk factor for Alzheimer's disease (AD). Human APOE gene is located on chromosome 19q13.1, a region linked to AD that also includes the LSR gene, which encodes the lipolysis-stimulated lipoprotein receptor (LSR). As an APOE receptor, LSR is involved in the regulation of lipid homeostasis in both periphery and brain. This study aimed to determine the potential interactions between 2 LSR genetic variants, rs34259399 and rs916147, and the APOE common polymorphism in 142 AD subjects (mean age: 73.16 ± 8.50 years) and 63 controls (mean age: 70.41 ± 8.49 years). A significant epistatic interaction was observed between APOE and both LSR variants, rs34259399 (beta = -0.95; p = 2 × 10) and rs916147 (beta = -0.83; p = 6.8 × 10). Interestingly, the interaction of LSR polymorphisms with APOE non-ε4 alleles increased AD risk. This indicates the existence of complex molecular interactions between t...
Physiological genomics, 2016
Perturbations of lipid homeostasis manifest as dyslipidemias and obesity, which are significant r... more Perturbations of lipid homeostasis manifest as dyslipidemias and obesity, which are significant risk factors for atherosclerosis and diabetes. Lipoprotein receptors in the liver are key players in the regulation of lipid homeostasis, among which the hepatic lipolysis stimulated lipoprotein receptor, LSR, was recently shown to play an important role in the removal of lipoproteins from the circulation during the postprandial phase. Since heterozygous LSR+/- mice demonstrate moderate dyslipidemia and develop higher body weight gain in response to high-fat diet compared with littermate LSR+/+ controls, we questioned if LSR heterozygosity could affect genes related to hepatic lipid metabolism. A target-specific qPCR array for 84 genes related to lipid metabolism was performed on mRNA isolated from livers of 6 mo old female LSR+/- mice and LSR+/+ littermates following a 6 wk period on a standard (STD) or high-fat diet (60% kcal, HFD). Of the 84 genes studied, 32 were significantly downreg...
Http Www Theses Fr, Dec 11, 2013
Life and Science
Over the last decades, the polyunsaturated fatty acids (PUFAs) have been largely explored not onl... more Over the last decades, the polyunsaturated fatty acids (PUFAs) have been largely explored not only for their nutritional value but also for the numerous biological functions and therapeutic effects. The serum and erythrocyte levels of PUFAs depend on the genetic control of metabolism as well as the dietary intake and are considered to reflect the health and disease status of an individual. Two families of PUFAs, omega-3 (n-3) and omega-6 (n-6), have gained much attention because of their involvement in the production of bioactive lipid mediators and therefore, a balanced omega-6/omega-3 ratio is crucial in maintaining the overall health of an individual. Omega-3 PUFAs, notably eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) have been shown to exert beneficial effects, possibly due to their lipid-lowering, anti-inflammatory, anti-hypertensive and cardioprotective effects, whereas omega-6 fatty acids such as arachidonic acid (ARA, 20:4n-6) exhibit the oppo...
Nutrients
Elevated serum cholesterol is a major risk factor for coronary heart diseases. Some Lactobacillus... more Elevated serum cholesterol is a major risk factor for coronary heart diseases. Some Lactobacillus strains with cholesterol-lowering potential have been isolated from artisanal food products. The purpose of this study was to isolate probiotic Lactobacillus strains from traditional yoghurt (dahi) and yogurt milk (lassi) and investigate the impact of these strains on the blood lipid profile and anti-obesity effect in a high cholesterol high fat diet model in Wistar rats. Eight candidate probiotic strains were chosen based on in vitro probiotic features and cholesterol reduction ability. By 16S rDNA sequencing, these strains were identified as Limosilactibacillus fermentum FM6, L. fermentum FM16, L. fermentum FM12, Lacticaseibacillus rhamnosus FM9, L. fermentum Y55, L. fermentum Y57, L. rhamnosus Y59, and L. fermentum Y63. The safety of these strains was investigated by feeding 2 × 108 CFU/mL in saline water for 28 days in a Wistar rat model. No bacterial translocation or any other adve...
Arteriosclerosis, Thrombosis, and Vascular Biology, 2012
The lipolysis stimulated lipoprotein receptor (LSR) plays an important role in hepatic uptake of ... more The lipolysis stimulated lipoprotein receptor (LSR) plays an important role in hepatic uptake of triglyceride (TG)-rich lipoproteins during the postprandial (PPL) phase. We recently reported the regulation of LSR by leptin, accompanied by changes in hepatic lipid metabolism. In this study, we sought to determine if a direct link exists between LSR and lipogenesis in the liver, focusing on ATP citrate lyase (ACL) and fatty acid synthase (FAS), two key enzymes for de novo fatty acid synthesis. Garcinia cambogia extract (GCE) contains hydroxycitric acid, an ACL potent inhibitor found to lower plasma TG and body weight in rodent and human studies. In female 10 wk-old C57BL/6Rj mice treated 30 days with corn oil emulsion containing 20 mg GCE (n=8), we observed reduced fasting (21%, p<0.03) and PPL (22%, p<0.02) plasma TG accompanied by a >1.5 fold (p<0.02) increase in liver membrane LSR protein as compared to controls (emulsion alone, n=8). While hepatic LDL-R protein was mod...
This work was conceptualized with the goal to investigate different fruits and vegetables for the... more This work was conceptualized with the goal to investigate different fruits and vegetables for their comparative investigation of total phenolic and total flavonoid contents. The total phenolic content of 9 fruits and 12 vegetables used in the current study was determined by Folin-Ciocalteau assay. In addition, total flavonoid content was identified through catechin and aluminum colorimetric analysis. The ratio among the phenolic and flavonoid contents of fruits and vegetables extracts were also analyzed. Our results showed that methanolic extract of Citrullus lanatus had higher contents of phenolics and flavonoids (215±1.24 mg GAE/100 g and 73±0.81 mg CE/100 g) than other fruits. Moreover, maturity process of fruits from unripened to fully ripened stage showed significant increase in the total phenolic and flavonoid contents. Fruits under study had shown flavonoids/phenolics ratio of 0.32, which indicates that these fruits contained about 32% of flavonoid contents. Among vegetables,...
'Essentials of Cancer Genomic, Computational Approaches and Precision Medicine, 2020
Cancer proteomics is a diverse and challenging field. It provides the promising tool that aids in... more Cancer proteomics is a diverse and challenging field. It provides the promising tool that aids in the understanding of the disease, yet early-stage diagnosis is still a question and crucial for successful treatment of cancer. Genomics aided with proteomics has emerged as a larger platform for understanding the disease spread, proliferation, metastasis, genomic aberrations, mutational changes, therapeutics, design drug delivery system, proteomic anomalies, structural changes, and signaling pathways and moving toward personalized approach. Biomarker identification and development of the panel are very precious in cancer treatment. Generally, biomarker identification, validation, and clinical examination are specific tools for accurate diagnostic, prognostic, and therapeutics. Present-day advances in proteomics and computational sciences have opened a gateway for the identification and quantitative analysis of protein variations associated with the complexities and heterogeneity of tumor development. Concept of personalized medicine is an emerging approach for cancer patient treatment, yet it has many challenges to overcome before its clinical application. Translational research in oncology still needs lots of quality research to overcome many challenges and for improvement in biomedical application and cancer patient care.
Frontiers in Bioscience, 2018
Introduction 2.1. Telomere structure 2.2. Telomere function 2.3. Telomere-binding proteins 2.4. T... more Introduction 2.1. Telomere structure 2.2. Telomere function 2.3. Telomere-binding proteins 2.4. Telomere lengthening 3. The telomere syndromes and treatment 4. Leukocyte tl and methods of mesurements 5. Determinants of TL 5.1. Biomarkers related to TL 6. Heritability and genetic variants associated with relative TL 7. TELOMEREs as a biomarker 7.1. Telomeres as aging biomarker 7.2. Telomeres as a biomarker in age-related diseases 7.3. Telomeres as a biomarker in cancer prognostic 7.4. Telomeres as a biomarker in cardiovascular diseases (CVD) 7.5. Telomeres as a biomarker in psychiatric disorders 7.6. Telomeres as a biomarker in Alzheimer's disease 8. Telomeres in anti-cancer treatment 8.1. Telomerase inhibitors 8.1.1. Telomerase inhibitor Imelstat (GRN163L) 8.1.2. G-quadruplex stabilisers 8.1.3. Natural products 8.2. Future perspectives and other therapies 9. Telomeres in treatment of other diseases 10. Commercial offer of telomere testing 11. Conclusions and new perspectives 12. References
FEBS Journal, 2012
Lsr and Lsr bind by comigration in gel electrophoresis (View interaction) Lsr binds to Lf by filt... more Lsr and Lsr bind by comigration in gel electrophoresis (View interaction) Lsr binds to Lf by filter binding (View interaction) Lf and Lsr colocalize by fluorescence microscopy (View interaction) Lsr physically interacts with VLDL by filter binding (View interaction
Pak. J. Bot, 2008
Germin and germin-like proteins constitute a large family of plant proteins which are also consid... more Germin and germin-like proteins constitute a large family of plant proteins which are also considered as germination markers due to their high expression levels during germination/early growth. These proteins are known to be involved in many stress related processes as well, but ...
The FASEB Journal, 2010
As a hepatic receptor for triglyceriderich lipoproteins, the lipolysis-stimulated lipoprotein rec... more As a hepatic receptor for triglyceriderich lipoproteins, the lipolysis-stimulated lipoprotein receptor (LSR) may be involved in the dynamics of lipid distribution between the liver and peripheral tissues. Here, we explore the potential role of leptin in regulating LSR. At physiological concentrations (1-10 ng/ml), leptin increased LSR protein and mRNA levels in Hepa1-6 cells through an ERK1/2-dependent and ␣-amanitin-sensitive pathway. In vivo, leptin treatment of C57BL6/Rj mice (1 g 2؋/d, 8 d) led to a significant increase in hepatic LSR mRNA and protein, decreased liver triglycerides and increased VLDL secretion as compared to controls. LSR ؉/؊ mice with elevated postprandial lipemia placed on a high-fat (60% kcal) diet exhibited accelerated weight gain and increased fat mass as compared to controls. While plasma leptin levels were increased 3-fold, hepatic leptin receptor protein levels and phosphorylation of ERK1/2 were significantly reduced. Therefore, leptin is an important regulator of LSR protein levels providing the means for the control of hepatic uptake of lipids during the postprandial phase. However, this may no longer be functional in LSR ؉/؊ mice placed under a chronic dietary fat load, suggesting that this animal model could be useful for the study of molecular mechanisms involved in peripheral leptin resistance.
International Journal of Molecular Sciences
Garcinia cambogia extract (GCE) is a popular weight-loss supplement that also lowers plasma trigl... more Garcinia cambogia extract (GCE) is a popular weight-loss supplement that also lowers plasma triglyceride (TG) levels. We hypothesized that GCE-mediated inhibition of ATP citrate lyase and thereby hepatic TG production could lead to compensatory mechanisms, including increased hepatic TG uptake via lipoprotein receptors. GCE (20 mg/day) administered 40 days orally to female C57BL/6Rj mice on a standard chow diet led to a decrease in both plasma fasting and post-prandial TG-rich lipoprotein levels, but with no significant change in body weight gain. Lipolysis stimulated lipoprotein receptor (LSR) protein levels, but not those of LDL-receptor, were increased as compared to controls. Mouse Hepa1-6 cells treated with the GCE active ingredient, hydroxycitrate, also led to increased LSR protein levels. Hepatic total cholesterol, TG, and muscle TG contents were higher in GCE-treated animals as compared to controls, whereas adipose TG levels were unchanged. LSR and LDL-receptor protein level...
The FASEB Journal, 2015
Elevated postprandial lipemia (PPL) as an important risk factor for cardiovascular disease has be... more Elevated postprandial lipemia (PPL) as an important risk factor for cardiovascular disease has been attributed to the accumulation of atherogenic remnant lipoproteins in the circulation. The hepati...
Neurobiology of aging, Jan 3, 2018
The ε4 allele of the apolipoprotein E (APOE) gene common polymorphism is the strongest genetic ri... more The ε4 allele of the apolipoprotein E (APOE) gene common polymorphism is the strongest genetic risk factor for Alzheimer's disease (AD). Human APOE gene is located on chromosome 19q13.1, a region linked to AD that also includes the LSR gene, which encodes the lipolysis-stimulated lipoprotein receptor (LSR). As an APOE receptor, LSR is involved in the regulation of lipid homeostasis in both periphery and brain. This study aimed to determine the potential interactions between 2 LSR genetic variants, rs34259399 and rs916147, and the APOE common polymorphism in 142 AD subjects (mean age: 73.16 ± 8.50 years) and 63 controls (mean age: 70.41 ± 8.49 years). A significant epistatic interaction was observed between APOE and both LSR variants, rs34259399 (beta = -0.95; p = 2 × 10) and rs916147 (beta = -0.83; p = 6.8 × 10). Interestingly, the interaction of LSR polymorphisms with APOE non-ε4 alleles increased AD risk. This indicates the existence of complex molecular interactions between t...
Physiological genomics, 2016
Perturbations of lipid homeostasis manifest as dyslipidemias and obesity, which are significant r... more Perturbations of lipid homeostasis manifest as dyslipidemias and obesity, which are significant risk factors for atherosclerosis and diabetes. Lipoprotein receptors in the liver are key players in the regulation of lipid homeostasis, among which the hepatic lipolysis stimulated lipoprotein receptor, LSR, was recently shown to play an important role in the removal of lipoproteins from the circulation during the postprandial phase. Since heterozygous LSR+/- mice demonstrate moderate dyslipidemia and develop higher body weight gain in response to high-fat diet compared with littermate LSR+/+ controls, we questioned if LSR heterozygosity could affect genes related to hepatic lipid metabolism. A target-specific qPCR array for 84 genes related to lipid metabolism was performed on mRNA isolated from livers of 6 mo old female LSR+/- mice and LSR+/+ littermates following a 6 wk period on a standard (STD) or high-fat diet (60% kcal, HFD). Of the 84 genes studied, 32 were significantly downreg...
Http Www Theses Fr, Dec 11, 2013
Life and Science
Over the last decades, the polyunsaturated fatty acids (PUFAs) have been largely explored not onl... more Over the last decades, the polyunsaturated fatty acids (PUFAs) have been largely explored not only for their nutritional value but also for the numerous biological functions and therapeutic effects. The serum and erythrocyte levels of PUFAs depend on the genetic control of metabolism as well as the dietary intake and are considered to reflect the health and disease status of an individual. Two families of PUFAs, omega-3 (n-3) and omega-6 (n-6), have gained much attention because of their involvement in the production of bioactive lipid mediators and therefore, a balanced omega-6/omega-3 ratio is crucial in maintaining the overall health of an individual. Omega-3 PUFAs, notably eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) have been shown to exert beneficial effects, possibly due to their lipid-lowering, anti-inflammatory, anti-hypertensive and cardioprotective effects, whereas omega-6 fatty acids such as arachidonic acid (ARA, 20:4n-6) exhibit the oppo...
Nutrients
Elevated serum cholesterol is a major risk factor for coronary heart diseases. Some Lactobacillus... more Elevated serum cholesterol is a major risk factor for coronary heart diseases. Some Lactobacillus strains with cholesterol-lowering potential have been isolated from artisanal food products. The purpose of this study was to isolate probiotic Lactobacillus strains from traditional yoghurt (dahi) and yogurt milk (lassi) and investigate the impact of these strains on the blood lipid profile and anti-obesity effect in a high cholesterol high fat diet model in Wistar rats. Eight candidate probiotic strains were chosen based on in vitro probiotic features and cholesterol reduction ability. By 16S rDNA sequencing, these strains were identified as Limosilactibacillus fermentum FM6, L. fermentum FM16, L. fermentum FM12, Lacticaseibacillus rhamnosus FM9, L. fermentum Y55, L. fermentum Y57, L. rhamnosus Y59, and L. fermentum Y63. The safety of these strains was investigated by feeding 2 × 108 CFU/mL in saline water for 28 days in a Wistar rat model. No bacterial translocation or any other adve...
Arteriosclerosis, Thrombosis, and Vascular Biology, 2012
The lipolysis stimulated lipoprotein receptor (LSR) plays an important role in hepatic uptake of ... more The lipolysis stimulated lipoprotein receptor (LSR) plays an important role in hepatic uptake of triglyceride (TG)-rich lipoproteins during the postprandial (PPL) phase. We recently reported the regulation of LSR by leptin, accompanied by changes in hepatic lipid metabolism. In this study, we sought to determine if a direct link exists between LSR and lipogenesis in the liver, focusing on ATP citrate lyase (ACL) and fatty acid synthase (FAS), two key enzymes for de novo fatty acid synthesis. Garcinia cambogia extract (GCE) contains hydroxycitric acid, an ACL potent inhibitor found to lower plasma TG and body weight in rodent and human studies. In female 10 wk-old C57BL/6Rj mice treated 30 days with corn oil emulsion containing 20 mg GCE (n=8), we observed reduced fasting (21%, p<0.03) and PPL (22%, p<0.02) plasma TG accompanied by a >1.5 fold (p<0.02) increase in liver membrane LSR protein as compared to controls (emulsion alone, n=8). While hepatic LDL-R protein was mod...
This work was conceptualized with the goal to investigate different fruits and vegetables for the... more This work was conceptualized with the goal to investigate different fruits and vegetables for their comparative investigation of total phenolic and total flavonoid contents. The total phenolic content of 9 fruits and 12 vegetables used in the current study was determined by Folin-Ciocalteau assay. In addition, total flavonoid content was identified through catechin and aluminum colorimetric analysis. The ratio among the phenolic and flavonoid contents of fruits and vegetables extracts were also analyzed. Our results showed that methanolic extract of Citrullus lanatus had higher contents of phenolics and flavonoids (215±1.24 mg GAE/100 g and 73±0.81 mg CE/100 g) than other fruits. Moreover, maturity process of fruits from unripened to fully ripened stage showed significant increase in the total phenolic and flavonoid contents. Fruits under study had shown flavonoids/phenolics ratio of 0.32, which indicates that these fruits contained about 32% of flavonoid contents. Among vegetables,...
'Essentials of Cancer Genomic, Computational Approaches and Precision Medicine, 2020
Cancer proteomics is a diverse and challenging field. It provides the promising tool that aids in... more Cancer proteomics is a diverse and challenging field. It provides the promising tool that aids in the understanding of the disease, yet early-stage diagnosis is still a question and crucial for successful treatment of cancer. Genomics aided with proteomics has emerged as a larger platform for understanding the disease spread, proliferation, metastasis, genomic aberrations, mutational changes, therapeutics, design drug delivery system, proteomic anomalies, structural changes, and signaling pathways and moving toward personalized approach. Biomarker identification and development of the panel are very precious in cancer treatment. Generally, biomarker identification, validation, and clinical examination are specific tools for accurate diagnostic, prognostic, and therapeutics. Present-day advances in proteomics and computational sciences have opened a gateway for the identification and quantitative analysis of protein variations associated with the complexities and heterogeneity of tumor development. Concept of personalized medicine is an emerging approach for cancer patient treatment, yet it has many challenges to overcome before its clinical application. Translational research in oncology still needs lots of quality research to overcome many challenges and for improvement in biomedical application and cancer patient care.
Frontiers in Bioscience, 2018
Introduction 2.1. Telomere structure 2.2. Telomere function 2.3. Telomere-binding proteins 2.4. T... more Introduction 2.1. Telomere structure 2.2. Telomere function 2.3. Telomere-binding proteins 2.4. Telomere lengthening 3. The telomere syndromes and treatment 4. Leukocyte tl and methods of mesurements 5. Determinants of TL 5.1. Biomarkers related to TL 6. Heritability and genetic variants associated with relative TL 7. TELOMEREs as a biomarker 7.1. Telomeres as aging biomarker 7.2. Telomeres as a biomarker in age-related diseases 7.3. Telomeres as a biomarker in cancer prognostic 7.4. Telomeres as a biomarker in cardiovascular diseases (CVD) 7.5. Telomeres as a biomarker in psychiatric disorders 7.6. Telomeres as a biomarker in Alzheimer's disease 8. Telomeres in anti-cancer treatment 8.1. Telomerase inhibitors 8.1.1. Telomerase inhibitor Imelstat (GRN163L) 8.1.2. G-quadruplex stabilisers 8.1.3. Natural products 8.2. Future perspectives and other therapies 9. Telomeres in treatment of other diseases 10. Commercial offer of telomere testing 11. Conclusions and new perspectives 12. References
FEBS Journal, 2012
Lsr and Lsr bind by comigration in gel electrophoresis (View interaction) Lsr binds to Lf by filt... more Lsr and Lsr bind by comigration in gel electrophoresis (View interaction) Lsr binds to Lf by filter binding (View interaction) Lf and Lsr colocalize by fluorescence microscopy (View interaction) Lsr physically interacts with VLDL by filter binding (View interaction
Pak. J. Bot, 2008
Germin and germin-like proteins constitute a large family of plant proteins which are also consid... more Germin and germin-like proteins constitute a large family of plant proteins which are also considered as germination markers due to their high expression levels during germination/early growth. These proteins are known to be involved in many stress related processes as well, but ...
The FASEB Journal, 2010
As a hepatic receptor for triglyceriderich lipoproteins, the lipolysis-stimulated lipoprotein rec... more As a hepatic receptor for triglyceriderich lipoproteins, the lipolysis-stimulated lipoprotein receptor (LSR) may be involved in the dynamics of lipid distribution between the liver and peripheral tissues. Here, we explore the potential role of leptin in regulating LSR. At physiological concentrations (1-10 ng/ml), leptin increased LSR protein and mRNA levels in Hepa1-6 cells through an ERK1/2-dependent and ␣-amanitin-sensitive pathway. In vivo, leptin treatment of C57BL6/Rj mice (1 g 2؋/d, 8 d) led to a significant increase in hepatic LSR mRNA and protein, decreased liver triglycerides and increased VLDL secretion as compared to controls. LSR ؉/؊ mice with elevated postprandial lipemia placed on a high-fat (60% kcal) diet exhibited accelerated weight gain and increased fat mass as compared to controls. While plasma leptin levels were increased 3-fold, hepatic leptin receptor protein levels and phosphorylation of ERK1/2 were significantly reduced. Therefore, leptin is an important regulator of LSR protein levels providing the means for the control of hepatic uptake of lipids during the postprandial phase. However, this may no longer be functional in LSR ؉/؊ mice placed under a chronic dietary fat load, suggesting that this animal model could be useful for the study of molecular mechanisms involved in peripheral leptin resistance.