Athletes often use branched-chain amino acid (BCAAs) supplements with a ratio of 2:1:1 (leucine:isoleucine:valine) for their impact on muscle building. Research suggests that by altering the ratio, an improvement in g...Athletes often use branched-chain amino acid (BCAAs) supplements with a ratio of 2:1:1 (leucine:isoleucine:valine) for their impact on muscle building. Research suggests that by altering the ratio, an improvement in glucose metabolism might be possible. The purpose of this study was to examine how isoleucine would influence glucose tolerance. We recruited healthy male (n = 13) and female (n = 5) participants who were asked to fast for 12 hours before coming to the laboratory. A fasting blood sample was collected, followed by the subjects consuming a breakfast containing 113 g carbohydrates, 8 g protein, 1.5 g fat, and BCAA powder in the 2:1:1 ratio (Control) or BCAA powder enriched with Isoleucine (2:6:1), both added to orange juice. The opposite meal was consumed on a second visit one week apart. Blood was collected at 30, 60, 90, and 120 minutes post-meal. No differences were observed between the Control and Isoleucine for changes in serum glucose or insulin response when examining all subjects together. However, when comparing between genders, males tended to have a significantly lower serum glucose response compared to females when consuming the Isoleucine, with no difference between the genders when consuming the Control. Also, males had significantly lower serum glucose responses when consuming the Isoleucine compared to when they consumed the Control, while females had significantly higher serum glucose responses when consuming the Isoleucine compared to when they consumed the Control. In general, males tended to have a lower serum insulin response than females when consuming both the Control and the Isoleucine. Our study indicates a significant difference in the way genders respond to BCAA supplementation, where isoleucine may improve glucose tolerance and insulin response in males but not females.展开更多
The thought of using branched-chain amino acids (BCAA) in the prevention and treatment of certain disorders is becoming increasingly popular. Individual BCAA use has been associated with improving glucose tolerance an...The thought of using branched-chain amino acids (BCAA) in the prevention and treatment of certain disorders is becoming increasingly popular. Individual BCAA use has been associated with improving glucose tolerance and liver disease. Previous studies have cited improvements in glucose metabolism with a single dose of L-isoleucine (ILE). However, it is still unclear whether chronic consumption of ILE has any direct benefit. The objective of this study was to examine the influence of chronic ILE supplementation alone or in combination with exercise on fasting serum glucose, insulin, lipids, and lipoprotein cholesterol levels;glucose tolerance;and hepatic lipids in rats. Male Sprague-Dawley rats (n = 40) were divided into Control (low fructose diet);High Fructose diet (HF);HF plus 1.5% ILE (HF + ILE);HF plus exercise (HF + EX);and HF plus 1.5% ILE and exercise (HF + ILE + EX). The HF diets consisted of 70% kcalories from fructose. After 6 weeks of treatment, no significant differences were observed between groups for changes in fasting serum glucose, insulin, lipids, or lipoprotein cholesterol levels. However, hepatic total cholesterol was significantly lower in the HF + ILE + EX compared to the Control and HF, while, the HF + ILE had significantly lower hepatic free cholesterol compared to the HF. We also found no differences between groups for serum glucose response following an oral glucose tolerance test. In conclusion, our study shows that ILE supplementation in rats does not influence serum glucose and lipid biomarkers but may have an influence on lipid metabolic pathways within the liver.展开更多
Decreasing the volume of media required to maintain cell viability not only reduces contamination of bioreactors from the upstream process,but may contribute to cost-containment measures in the biopharmaceutical indus...Decreasing the volume of media required to maintain cell viability not only reduces contamination of bioreactors from the upstream process,but may contribute to cost-containment measures in the biopharmaceutical industry.Based on our recent finding that dextran-containing nanocarriers increased CHO cell density up to 20 fold compared to its cellulose-containing microcarrier counterpart(manuscript submitted),we then investigated the possibility of reducing media volume to maintain cell viability,by utilizing the same dextran-based nanocarrier prepared from a self assembling nanoemulsion(SANE)method,and an adherent Chinese hamster ovary(CHO)cell culture line to evaluate media volume requirements.At the same 60 mL volume of media,cell viability after day 3 was 6 fold greater in CHO cells exposed to dextran-containing nanocarriers compared to cellulose-based microcarriers.When CHO cells were exposed to 60 mL of media containing dextran-based nanocarriers compared to 100 mL of media for cellulose-microcarriers,at day 6,cell density was up to 7 fold greater.Similarly,cell lysate protein concentrations at day 6 was nearly 3 fold greater for CHO cells exposed to dextran-containing nanocarriers compared to the cellulose-based microcarriers.Furthermore,nanocarriers had 59%greater glucose concentration,used as a measure of the polymer dextran and cellulose content levels in the nanocarriers and microcarriers,respectively.In conclusion,nanocarriers with increased numbers of dextran molecules,developed in these studies may be useful to further optimize media volume requirements for maximum culture growth.展开更多
Microcarriers containing cellulose-derived materials have been successfully applied to enhance the growth of anchorage-dependent cells maintained especially in bioreactors.By replacing microcarriers with nanocarriers ...Microcarriers containing cellulose-derived materials have been successfully applied to enhance the growth of anchorage-dependent cells maintained especially in bioreactors.By replacing microcarriers with nanocarriers containing dextran,we hypothesized that the density of the anchorage-dependent cells would rise dramatically because the decreased particle size and associated enhancement in surface to volume ratios of nanoparticles contained within the nanoemulsion-based nanocarriers would increase the number of dextran molecules for the anchorage-dependent cells to attach to.Our studies utilized self-assembly nanoemulsions(SANE)formed by a modified phase inversion temperature(PIT)process to produce dextran oil and surfactant-containing nanocarriers having mean particle sizes of 26 nm compared to microcarriers which were greater than 6000 nm.Our results demonstrated that dextran-containing nanocarriers allowed up to 10 fold greater cell density,12% more media lactate concentration,83%higher cell lysate protein and 59% greater glucose concentration,used as a measure of polymer levels in the nanocarriers compared to microcarriers.In conclusion,nanocarriers with increased numbers of dextran molecules,developed in these studies may be useful to further increase the production of anchorage-dependent animal cell-derived products or production of mass cell growth for other applications.展开更多
Recent innovations in bone tissue engineering have introduced biomaterials that generate oxygen to substitute vasculature.This strategy provides the immediate oxygen required for tissue viability and graft maturation....Recent innovations in bone tissue engineering have introduced biomaterials that generate oxygen to substitute vasculature.This strategy provides the immediate oxygen required for tissue viability and graft maturation.Here we demonstrate a novel oxygen-generating tissue scaffold with predictable oxygen release kinetics and modular material properties.These hydrogel scaffolds were reinforced with microparticles comprised of emulsified calcium peroxide(CaO_(2))within polycaprolactone(PCL).The alterations of the assembled materials produced constructs within 5±0.81 kPa to 34±0.9 kPa in mechanical strength.The mass swelling ratios varied between 11%and 25%.Our in vitro and in vivo results revealed consistent tissue viability,metabolic activity,and osteogenic differentiation over two weeks.The optimized in vitro cell culture system remained stable at pH 8-9.The in vivo rodent models demonstrated that these scaffolds support a 70 mm^(3) bone volume that was comparable to the native bone and yielded over 90%regeneration in critical size cranial defects.Furthermore,the in vivo bone remodeling and vascularization results were validated by tartrate-resistant acid phosphatase(TRAP)and vascular endothelial growth factor(VEGF)staining.The promising results of this work are translatable to a repertoire of regenerative medicine applications including advancement and expansion of bone substitutes and disease models.展开更多
文摘Athletes often use branched-chain amino acid (BCAAs) supplements with a ratio of 2:1:1 (leucine:isoleucine:valine) for their impact on muscle building. Research suggests that by altering the ratio, an improvement in glucose metabolism might be possible. The purpose of this study was to examine how isoleucine would influence glucose tolerance. We recruited healthy male (n = 13) and female (n = 5) participants who were asked to fast for 12 hours before coming to the laboratory. A fasting blood sample was collected, followed by the subjects consuming a breakfast containing 113 g carbohydrates, 8 g protein, 1.5 g fat, and BCAA powder in the 2:1:1 ratio (Control) or BCAA powder enriched with Isoleucine (2:6:1), both added to orange juice. The opposite meal was consumed on a second visit one week apart. Blood was collected at 30, 60, 90, and 120 minutes post-meal. No differences were observed between the Control and Isoleucine for changes in serum glucose or insulin response when examining all subjects together. However, when comparing between genders, males tended to have a significantly lower serum glucose response compared to females when consuming the Isoleucine, with no difference between the genders when consuming the Control. Also, males had significantly lower serum glucose responses when consuming the Isoleucine compared to when they consumed the Control, while females had significantly higher serum glucose responses when consuming the Isoleucine compared to when they consumed the Control. In general, males tended to have a lower serum insulin response than females when consuming both the Control and the Isoleucine. Our study indicates a significant difference in the way genders respond to BCAA supplementation, where isoleucine may improve glucose tolerance and insulin response in males but not females.
文摘The thought of using branched-chain amino acids (BCAA) in the prevention and treatment of certain disorders is becoming increasingly popular. Individual BCAA use has been associated with improving glucose tolerance and liver disease. Previous studies have cited improvements in glucose metabolism with a single dose of L-isoleucine (ILE). However, it is still unclear whether chronic consumption of ILE has any direct benefit. The objective of this study was to examine the influence of chronic ILE supplementation alone or in combination with exercise on fasting serum glucose, insulin, lipids, and lipoprotein cholesterol levels;glucose tolerance;and hepatic lipids in rats. Male Sprague-Dawley rats (n = 40) were divided into Control (low fructose diet);High Fructose diet (HF);HF plus 1.5% ILE (HF + ILE);HF plus exercise (HF + EX);and HF plus 1.5% ILE and exercise (HF + ILE + EX). The HF diets consisted of 70% kcalories from fructose. After 6 weeks of treatment, no significant differences were observed between groups for changes in fasting serum glucose, insulin, lipids, or lipoprotein cholesterol levels. However, hepatic total cholesterol was significantly lower in the HF + ILE + EX compared to the Control and HF, while, the HF + ILE had significantly lower hepatic free cholesterol compared to the HF. We also found no differences between groups for serum glucose response following an oral glucose tolerance test. In conclusion, our study shows that ILE supplementation in rats does not influence serum glucose and lipid biomarkers but may have an influence on lipid metabolic pathways within the liver.
文摘Decreasing the volume of media required to maintain cell viability not only reduces contamination of bioreactors from the upstream process,but may contribute to cost-containment measures in the biopharmaceutical industry.Based on our recent finding that dextran-containing nanocarriers increased CHO cell density up to 20 fold compared to its cellulose-containing microcarrier counterpart(manuscript submitted),we then investigated the possibility of reducing media volume to maintain cell viability,by utilizing the same dextran-based nanocarrier prepared from a self assembling nanoemulsion(SANE)method,and an adherent Chinese hamster ovary(CHO)cell culture line to evaluate media volume requirements.At the same 60 mL volume of media,cell viability after day 3 was 6 fold greater in CHO cells exposed to dextran-containing nanocarriers compared to cellulose-based microcarriers.When CHO cells were exposed to 60 mL of media containing dextran-based nanocarriers compared to 100 mL of media for cellulose-microcarriers,at day 6,cell density was up to 7 fold greater.Similarly,cell lysate protein concentrations at day 6 was nearly 3 fold greater for CHO cells exposed to dextran-containing nanocarriers compared to the cellulose-based microcarriers.Furthermore,nanocarriers had 59%greater glucose concentration,used as a measure of the polymer dextran and cellulose content levels in the nanocarriers and microcarriers,respectively.In conclusion,nanocarriers with increased numbers of dextran molecules,developed in these studies may be useful to further optimize media volume requirements for maximum culture growth.
文摘Microcarriers containing cellulose-derived materials have been successfully applied to enhance the growth of anchorage-dependent cells maintained especially in bioreactors.By replacing microcarriers with nanocarriers containing dextran,we hypothesized that the density of the anchorage-dependent cells would rise dramatically because the decreased particle size and associated enhancement in surface to volume ratios of nanoparticles contained within the nanoemulsion-based nanocarriers would increase the number of dextran molecules for the anchorage-dependent cells to attach to.Our studies utilized self-assembly nanoemulsions(SANE)formed by a modified phase inversion temperature(PIT)process to produce dextran oil and surfactant-containing nanocarriers having mean particle sizes of 26 nm compared to microcarriers which were greater than 6000 nm.Our results demonstrated that dextran-containing nanocarriers allowed up to 10 fold greater cell density,12% more media lactate concentration,83%higher cell lysate protein and 59% greater glucose concentration,used as a measure of polymer levels in the nanocarriers compared to microcarriers.In conclusion,nanocarriers with increased numbers of dextran molecules,developed in these studies may be useful to further increase the production of anchorage-dependent animal cell-derived products or production of mass cell growth for other applications.
基金This research was partially supported by the American Heart Association(AHA)(19TPA34910111)the University of Massachusetts Lowell faculty start-up funds,and the National Institutes of Health(NIH)(R01DE030129)。
文摘Recent innovations in bone tissue engineering have introduced biomaterials that generate oxygen to substitute vasculature.This strategy provides the immediate oxygen required for tissue viability and graft maturation.Here we demonstrate a novel oxygen-generating tissue scaffold with predictable oxygen release kinetics and modular material properties.These hydrogel scaffolds were reinforced with microparticles comprised of emulsified calcium peroxide(CaO_(2))within polycaprolactone(PCL).The alterations of the assembled materials produced constructs within 5±0.81 kPa to 34±0.9 kPa in mechanical strength.The mass swelling ratios varied between 11%and 25%.Our in vitro and in vivo results revealed consistent tissue viability,metabolic activity,and osteogenic differentiation over two weeks.The optimized in vitro cell culture system remained stable at pH 8-9.The in vivo rodent models demonstrated that these scaffolds support a 70 mm^(3) bone volume that was comparable to the native bone and yielded over 90%regeneration in critical size cranial defects.Furthermore,the in vivo bone remodeling and vascularization results were validated by tartrate-resistant acid phosphatase(TRAP)and vascular endothelial growth factor(VEGF)staining.The promising results of this work are translatable to a repertoire of regenerative medicine applications including advancement and expansion of bone substitutes and disease models.
