BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats...BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats, we found that the supplementation of sodium salicylate is associated with a reduction of plasma malondialdehyde (MDA), a marker of oxidative stress. Few studies have investigated the effects of salicylates on oxidative stress levels in insulin-resistant animal models. This study aimed to assess the effect of sodium salicylate on insulin sensitivity and to explore the potential mechanism by which it improves hepatic and peripheral insulin resistance. METHODS: Intralipid+heparin (IH), saline (SAL), or intralipid+heparin+sodium salicylate (IHS) were separately infused for 7 hours in normal Wistar rats. During the last 2 hours of the infusion, hyperinsulinemic-euglycemic clamping was 3 performed with [6-(3)H] glucose tracer. Plasma glucose was measured using the glucose oxygenase method. Plasma insulin and C-peptide were determined by radioimmunoassay. MDA levels and glutathione peroxidase (GSH-PX) activity in the liver and skeletal muscle were measured with colorimetric kits. RESULTS: Compared with infusion of SAL, IH infusion increased hepatic glucose production (HGP), and decreased glucose utilization (GU) (P<0.05). The elevation of plasma free fatty acids increased the MDA levels and decreased the GSH-PX activity in the liver and muscle (P<0.01). Sodium salicylate treatment decreased HGP, elevated GU (P<0.05), reduced MDA content by 60% (P<0.01), and increased the GSH-PX activity by 35% (P<0.05). CONCLUSIONS: Short-term elevation of fatty acids induces insulin resistance by enhancing oxidative stress levels in the liver and muscle. The administration of the anti-inflammatory drug sodium salicylate reduces the degree of oxidative stress, therefore improving hepatic and peripheral insulin resistance. IKK-beta and NF-kappa B provide potential pathogenic links to oxidative stress.展开更多
Objective: To investigate the correlation of serum free fatty acid content with glucolipid metabolism, microinflammation and oxidative stress state in patients with type 2 diabetes mellitus. Methods: A total of 189 pa...Objective: To investigate the correlation of serum free fatty acid content with glucolipid metabolism, microinflammation and oxidative stress state in patients with type 2 diabetes mellitus. Methods: A total of 189 patients with type 2 diabetes mellitus who were treated in this hospital between August 2015 and February 2018 were chosen as type 2 diabetes mellitus group, and 100 healthy subjects who received physical examination in this hospital during the same period were chosen as the normal control group. The differences in serum levels of FFA, glucolipid metabolism indexes, microinflammation indexes and oxidative stress indexes were compared between the two groups of subjects, and correlation analysis was adopted to judge the inner link of serum FFA content with glucolipid metabolism, microinflammation and oxidative stress state in patients with type 2 diabetes mellitus. Results: Serum FFA content of type 2 diabetes mellitus group was higher than that of control group;serum glucolipid metabolism indexes FPG, 2hPG, TC and LDL-C levels were higher than those of normal control group whereas HDL-C level was lower than that of control group;serum microinflammation indexes IL-1β, IL-6, IL-10, IL-15 and TNF-α contents were higher than those of control group;serum oxidative stress indexes GSH-Px and SOD contents were lower than those of control group whereas ROS and MDA contents were higher than those of control group. Pearson test showed that the serum FFA content of patients with type 2 diabetes mellitus was directly correlated with the contents of glucolipid metabolism, microinflammation and oxidative stress indexes. Conclusion: Serum FFA content significantly increases in patients with type 2 diabetes mellitus, and the specific content was directly correlated with glycolipid metabolism, microinflammation, oxidative stress and other illness indexes.展开更多
Metabolism of free fatty acids（FFAs） is related to several important physiological events and therefore their quantitaion in biological samples arouses extensive interest and efforts.Existing gas chromatography with...Metabolism of free fatty acids（FFAs） is related to several important physiological events and therefore their quantitaion in biological samples arouses extensive interest and efforts.Existing gas chromatography with flame ionization detector（GC-FID） methods for the analysis of FFAs normally require derivatization of them in order to lower boiling points.But this extra procedure tends to induce additional error and it is laborious and time-consuming.A derivatization-free method was therefore established in the present investigation to determine FFAs in human plasma by capillary（GC-FID）.After extraction of FFAs from plasma,a highly polar FFAP（free fatty acid in plasma） column was employed to directly quantitate FFAs concentration,free from derivatization reaction.All sample pretreatments were carried out at room temperature,improving recovery of short-chain FFAs.Heptadecanoic acid（C17：0） was employed as internal standard,and the proposed method was validated for recovery,precision,sensitivity,stabi-lity,and linearity.Validation data show that it is suitable for clinical study that has been applied to the evaluation of FFAs levels in plasma of diabetic nephropathy（DN） patients during the course of treatment.Forty-seven patients diagnosed with DN were admitted to the double-blind experiment.Control group（n=17） underwent solely basic treatment and the patients did not show significant change in FFAs concentration during six months of treatment.Experiment group（n=30） was supplied with traditional Chinese medicine besides basic treatment.After six months of medication,their plasma concentration of palmitic acid（C16：0）,stearic acid（C18：0） and oleic acid（C18：1n-9） decreased while linolenic acid（C18：3n-3） increased significantly（P〈0.05）.These four compounds could be served as biomar-kers in the evaluation of drug efficacy,and their quantitation in plasma may provide additional information for disease progression in DN patients.展开更多
The role of free fatty acids (FFAs) as a source of energy and their functions in energy transport within the body are well established. Equally important is a role that FFAs play in oxidative stress following cell mem...The role of free fatty acids (FFAs) as a source of energy and their functions in energy transport within the body are well established. Equally important is a role that FFAs play in oxidative stress following cell membrane depolarization. FFAs are physiologically active, not only as nutritional components, but also as molecules involved in cell signaling and stabilization of membranes via palmitoylation and myristoylation. Protein palmitoylation is involved in numerous cellular processes, including apoptosis, and neuronal transmission. Besides nuclear peroxisome proliferator-activated receptors that mediate the biological effects of FFAs, G protein-coupled receptors (GPCRs) that are activated by FFA, have been recently identified. Those multiple FFA receptors (FFARs), which function on the cell surface as activated FFAs, play significant roles in the regulation of energy metabolism and mediate a wide range of important metabolic processes. FFARs have been targeted in drug development for the treatment of type 2 diabetes and metabolic syndrome. FFAs upregulate transcription of uncoupling proteins, increasing their expression in brain, cardiac, and skeletal muscle that may be protective or cytotoxic, depending on the cellular energy state. Recently, FFA effects on the endothelial function and dysfunction are being recognized. FFAs play a key role in endothelium-dependent nitric oxide production. A disturbance of endothelial function, due to an imbalance in production and release of relaxing and constricting factors, has implications in the development of cardiovascular problems, such as hypertension, as well as neurotoxicity following loss of blood-brain barrier integrity. This review presents information on broad range of FFAs actions of prime importance for physiological processes. Understanding of FFA functions in the body is crucial for developing new therapeutic strategies against several metabolic disorders.展开更多
This study proposed a strategy based on simple chemical derivatization coupled with neutral loss scan tandem to electrospray ionization source of mass spectrometer (NLS-ESI-MS/MS) for rapid and sensitive detection of ...This study proposed a strategy based on simple chemical derivatization coupled with neutral loss scan tandem to electrospray ionization source of mass spectrometer (NLS-ESI-MS/MS) for rapid and sensitive detection of free fatty acids (FFAs) in coldpressed rapeseed oils without sample purification and enrichment. The method was applied to investigate contents of FFAs and their changes in cold-pressed rapeseed oil pretreated by microwave. Results showed that main FFAs in rapeseed oil control samples were myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3). The highest content of C18:1 was 7163.69 nmol/g and C18:2 was 5221.18 nmol/g among 8 oil samples. FFAs generally increased after microwave pretreatment except C14:0 in oil sample of ‘Xinyou 17’ and ‘Suyou 6’. C18:1 and C18:2 significantly changed (P<0.05) after microwave pretreatment. With this established simple,practical and reliable analysis approach, changes of FFAs would be monitored to ensure safety and quality of edible oils. A powerful tool is provided for thermal degradation mechanism research of edible oils.展开更多
Deterioration and loss of quality of vegetable oil is a big challenge in the food industry.This study investigated the synthesis of nickel ferrite(Ni Fe_(2)_(O4))via co-precipitation method and its use for the removal...Deterioration and loss of quality of vegetable oil is a big challenge in the food industry.This study investigated the synthesis of nickel ferrite(Ni Fe_(2)_(O4))via co-precipitation method and its use for the removal of free fatty acids(FFAs)in deteriorated vegetable oil.Ni Fe2 O4 was characterized using Fourier transformed infrared spectroscopy(FTIR),X-ray diffraction(XRD),thermogravimetric(TG)analysis,Brunauer–Emm ett–Teller(BET)surface area,transmission electron microscopy(TEM),scanning electron microscopy(SEM)and energy-dispersive X-ray spectroscopy(EDX).Synthesis of Ni Fe_(2)_(O4)was confirmed by characterization,which revealed a BET surface area of 16.30 m^(2)·g^(-1)and crystallite size of 29 nm.Ni Fe_(2)_(O4)exhibited an adsorption capacity of 145.20 L·kg^(-1)towards FFAs with an 80.69%removal in a process,which obeys Langmuir isotherm and can be described by the pseudo-second-order kinetic model.The process has enthalpy(DH)of 11.251 k Jámolà1 and entropy(DS)of 0.038 k J·mol^(-1)K^(-1)with negative free energy change(DG),which suggests the process to be spontaneous and endothermic.The quantum chemical computation analysis via density functional theory further revealed the sorption mechanism of FFAs by Ni Fe_(2)_(O4)occurred via donor–acceptor interaction,which may be described by the lowest unoccupied molecular orbital(LUMO)and the highest occupied molecular orbital(HOMO).The study showed Ni Fe_(2)_(O4)to be a potential means that can remove FFAs from deteriorated vegetable oil.展开更多
Alkaline microcrystalline cellulose (AMC) was used as adsorption agent in deacidification in this paper. Changes of isothermal adsorption of free fatty acids (FFA) and micro-components (α-tocopherol and β-sitosterol...Alkaline microcrystalline cellulose (AMC) was used as adsorption agent in deacidification in this paper. Changes of isothermal adsorption of free fatty acids (FFA) and micro-components (α-tocopherol and β-sitosterol) in rapeseed oil on AMC were investigated. The results showed that difference in initial micro-component contents would not change adsorption characteristics of AMC to FFA. Adsorption characteristics were always as the following: Langmuir equation was more suitable to static adsorption process of AMC to FFA than Freundlich equation; moderate temperature (30-40oC) was advantageous to adsorption; adsorption was a preferential one. The highest retention rate of α-tocopherol and β-sitosterol during absorptive deacidification by AMC were 99.5% and 91.5% respectively. Therefore, AMC was suitable for adsorption deacidification application of rapeseed oil.展开更多
Cation ion-exchange resin particles （CERP）/polyethersulfone （PES） hybrid catalytic membranes were prepared by immerse phase inversion for the esterification of different free fatty acids （FFAs） （such as, dodeca...Cation ion-exchange resin particles （CERP）/polyethersulfone （PES） hybrid catalytic membranes were prepared by immerse phase inversion for the esterification of different free fatty acids （FFAs） （such as, dodecanoic acid, tetradecanoic acid, hexadecanoic acid and octadecadienoic acid） with methanol. The membranes were characterized by SEM, ion-exchange capacity and swelling degree test. It is found that dodecanoic acid has the highest FFAs conversion among the four acids for its stronger acidic and reactivity. Different effects of membrane annealing temperature, reaction temperature, molar ratio of methanol to FFAs and catalytic membrane loading on the esterification were investigated by the esterification of dodecanoic acid with methanol. The dodecanoic acid conversion reaches 97.5% trader the optimal condition when the esterification reaction lasted for 8 h.展开更多
基金supported by a grant from the Bureau of Education of Liaoning Province,China (No.20060999)
文摘BACKGROUND: It has been reported that high-dose salicylates improve free fatty acids (FFAs)-induced insulin resistance and beta-cell dysfunction in vitro, but the mechanism remains uncertain. In insulin-resistant rats, we found that the supplementation of sodium salicylate is associated with a reduction of plasma malondialdehyde (MDA), a marker of oxidative stress. Few studies have investigated the effects of salicylates on oxidative stress levels in insulin-resistant animal models. This study aimed to assess the effect of sodium salicylate on insulin sensitivity and to explore the potential mechanism by which it improves hepatic and peripheral insulin resistance. METHODS: Intralipid+heparin (IH), saline (SAL), or intralipid+heparin+sodium salicylate (IHS) were separately infused for 7 hours in normal Wistar rats. During the last 2 hours of the infusion, hyperinsulinemic-euglycemic clamping was 3 performed with [6-(3)H] glucose tracer. Plasma glucose was measured using the glucose oxygenase method. Plasma insulin and C-peptide were determined by radioimmunoassay. MDA levels and glutathione peroxidase (GSH-PX) activity in the liver and skeletal muscle were measured with colorimetric kits. RESULTS: Compared with infusion of SAL, IH infusion increased hepatic glucose production (HGP), and decreased glucose utilization (GU) (P<0.05). The elevation of plasma free fatty acids increased the MDA levels and decreased the GSH-PX activity in the liver and muscle (P<0.01). Sodium salicylate treatment decreased HGP, elevated GU (P<0.05), reduced MDA content by 60% (P<0.01), and increased the GSH-PX activity by 35% (P<0.05). CONCLUSIONS: Short-term elevation of fatty acids induces insulin resistance by enhancing oxidative stress levels in the liver and muscle. The administration of the anti-inflammatory drug sodium salicylate reduces the degree of oxidative stress, therefore improving hepatic and peripheral insulin resistance. IKK-beta and NF-kappa B provide potential pathogenic links to oxidative stress.
文摘Objective: To investigate the correlation of serum free fatty acid content with glucolipid metabolism, microinflammation and oxidative stress state in patients with type 2 diabetes mellitus. Methods: A total of 189 patients with type 2 diabetes mellitus who were treated in this hospital between August 2015 and February 2018 were chosen as type 2 diabetes mellitus group, and 100 healthy subjects who received physical examination in this hospital during the same period were chosen as the normal control group. The differences in serum levels of FFA, glucolipid metabolism indexes, microinflammation indexes and oxidative stress indexes were compared between the two groups of subjects, and correlation analysis was adopted to judge the inner link of serum FFA content with glucolipid metabolism, microinflammation and oxidative stress state in patients with type 2 diabetes mellitus. Results: Serum FFA content of type 2 diabetes mellitus group was higher than that of control group;serum glucolipid metabolism indexes FPG, 2hPG, TC and LDL-C levels were higher than those of normal control group whereas HDL-C level was lower than that of control group;serum microinflammation indexes IL-1β, IL-6, IL-10, IL-15 and TNF-α contents were higher than those of control group;serum oxidative stress indexes GSH-Px and SOD contents were lower than those of control group whereas ROS and MDA contents were higher than those of control group. Pearson test showed that the serum FFA content of patients with type 2 diabetes mellitus was directly correlated with the contents of glucolipid metabolism, microinflammation and oxidative stress indexes. Conclusion: Serum FFA content significantly increases in patients with type 2 diabetes mellitus, and the specific content was directly correlated with glycolipid metabolism, microinflammation, oxidative stress and other illness indexes.
基金Supported by the National Basic Research Program of China(Nos.2007CB511903,2005CB523503)the International Cooperation Project of Ministry of Science and Technology of China(No.S2010GR0583)the National Natural Science Founda- tion of China(Nos.90709045,20805026)
文摘Metabolism of free fatty acids（FFAs） is related to several important physiological events and therefore their quantitaion in biological samples arouses extensive interest and efforts.Existing gas chromatography with flame ionization detector（GC-FID） methods for the analysis of FFAs normally require derivatization of them in order to lower boiling points.But this extra procedure tends to induce additional error and it is laborious and time-consuming.A derivatization-free method was therefore established in the present investigation to determine FFAs in human plasma by capillary（GC-FID）.After extraction of FFAs from plasma,a highly polar FFAP（free fatty acid in plasma） column was employed to directly quantitate FFAs concentration,free from derivatization reaction.All sample pretreatments were carried out at room temperature,improving recovery of short-chain FFAs.Heptadecanoic acid（C17：0） was employed as internal standard,and the proposed method was validated for recovery,precision,sensitivity,stabi-lity,and linearity.Validation data show that it is suitable for clinical study that has been applied to the evaluation of FFAs levels in plasma of diabetic nephropathy（DN） patients during the course of treatment.Forty-seven patients diagnosed with DN were admitted to the double-blind experiment.Control group（n=17） underwent solely basic treatment and the patients did not show significant change in FFAs concentration during six months of treatment.Experiment group（n=30） was supplied with traditional Chinese medicine besides basic treatment.After six months of medication,their plasma concentration of palmitic acid（C16：0）,stearic acid（C18：0） and oleic acid（C18：1n-9） decreased while linolenic acid（C18：3n-3） increased significantly（P〈0.05）.These four compounds could be served as biomar-kers in the evaluation of drug efficacy,and their quantitation in plasma may provide additional information for disease progression in DN patients.
文摘The role of free fatty acids (FFAs) as a source of energy and their functions in energy transport within the body are well established. Equally important is a role that FFAs play in oxidative stress following cell membrane depolarization. FFAs are physiologically active, not only as nutritional components, but also as molecules involved in cell signaling and stabilization of membranes via palmitoylation and myristoylation. Protein palmitoylation is involved in numerous cellular processes, including apoptosis, and neuronal transmission. Besides nuclear peroxisome proliferator-activated receptors that mediate the biological effects of FFAs, G protein-coupled receptors (GPCRs) that are activated by FFA, have been recently identified. Those multiple FFA receptors (FFARs), which function on the cell surface as activated FFAs, play significant roles in the regulation of energy metabolism and mediate a wide range of important metabolic processes. FFARs have been targeted in drug development for the treatment of type 2 diabetes and metabolic syndrome. FFAs upregulate transcription of uncoupling proteins, increasing their expression in brain, cardiac, and skeletal muscle that may be protective or cytotoxic, depending on the cellular energy state. Recently, FFA effects on the endothelial function and dysfunction are being recognized. FFAs play a key role in endothelium-dependent nitric oxide production. A disturbance of endothelial function, due to an imbalance in production and release of relaxing and constricting factors, has implications in the development of cardiovascular problems, such as hypertension, as well as neurotoxicity following loss of blood-brain barrier integrity. This review presents information on broad range of FFAs actions of prime importance for physiological processes. Understanding of FFA functions in the body is crucial for developing new therapeutic strategies against several metabolic disorders.
文摘This study proposed a strategy based on simple chemical derivatization coupled with neutral loss scan tandem to electrospray ionization source of mass spectrometer (NLS-ESI-MS/MS) for rapid and sensitive detection of free fatty acids (FFAs) in coldpressed rapeseed oils without sample purification and enrichment. The method was applied to investigate contents of FFAs and their changes in cold-pressed rapeseed oil pretreated by microwave. Results showed that main FFAs in rapeseed oil control samples were myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3). The highest content of C18:1 was 7163.69 nmol/g and C18:2 was 5221.18 nmol/g among 8 oil samples. FFAs generally increased after microwave pretreatment except C14:0 in oil sample of ‘Xinyou 17’ and ‘Suyou 6’. C18:1 and C18:2 significantly changed (P<0.05) after microwave pretreatment. With this established simple,practical and reliable analysis approach, changes of FFAs would be monitored to ensure safety and quality of edible oils. A powerful tool is provided for thermal degradation mechanism research of edible oils.
文摘Deterioration and loss of quality of vegetable oil is a big challenge in the food industry.This study investigated the synthesis of nickel ferrite(Ni Fe_(2)_(O4))via co-precipitation method and its use for the removal of free fatty acids(FFAs)in deteriorated vegetable oil.Ni Fe2 O4 was characterized using Fourier transformed infrared spectroscopy(FTIR),X-ray diffraction(XRD),thermogravimetric(TG)analysis,Brunauer–Emm ett–Teller(BET)surface area,transmission electron microscopy(TEM),scanning electron microscopy(SEM)and energy-dispersive X-ray spectroscopy(EDX).Synthesis of Ni Fe_(2)_(O4)was confirmed by characterization,which revealed a BET surface area of 16.30 m^(2)·g^(-1)and crystallite size of 29 nm.Ni Fe_(2)_(O4)exhibited an adsorption capacity of 145.20 L·kg^(-1)towards FFAs with an 80.69%removal in a process,which obeys Langmuir isotherm and can be described by the pseudo-second-order kinetic model.The process has enthalpy(DH)of 11.251 k Jámolà1 and entropy(DS)of 0.038 k J·mol^(-1)K^(-1)with negative free energy change(DG),which suggests the process to be spontaneous and endothermic.The quantum chemical computation analysis via density functional theory further revealed the sorption mechanism of FFAs by Ni Fe_(2)_(O4)occurred via donor–acceptor interaction,which may be described by the lowest unoccupied molecular orbital(LUMO)and the highest occupied molecular orbital(HOMO).The study showed Ni Fe_(2)_(O4)to be a potential means that can remove FFAs from deteriorated vegetable oil.
文摘Alkaline microcrystalline cellulose (AMC) was used as adsorption agent in deacidification in this paper. Changes of isothermal adsorption of free fatty acids (FFA) and micro-components (α-tocopherol and β-sitosterol) in rapeseed oil on AMC were investigated. The results showed that difference in initial micro-component contents would not change adsorption characteristics of AMC to FFA. Adsorption characteristics were always as the following: Langmuir equation was more suitable to static adsorption process of AMC to FFA than Freundlich equation; moderate temperature (30-40oC) was advantageous to adsorption; adsorption was a preferential one. The highest retention rate of α-tocopherol and β-sitosterol during absorptive deacidification by AMC were 99.5% and 91.5% respectively. Therefore, AMC was suitable for adsorption deacidification application of rapeseed oil.
基金Project(ZR2011BL005) supported by the Natural Science Foundation of Shandong Province,China
文摘Cation ion-exchange resin particles （CERP）/polyethersulfone （PES） hybrid catalytic membranes were prepared by immerse phase inversion for the esterification of different free fatty acids （FFAs） （such as, dodecanoic acid, tetradecanoic acid, hexadecanoic acid and octadecadienoic acid） with methanol. The membranes were characterized by SEM, ion-exchange capacity and swelling degree test. It is found that dodecanoic acid has the highest FFAs conversion among the four acids for its stronger acidic and reactivity. Different effects of membrane annealing temperature, reaction temperature, molar ratio of methanol to FFAs and catalytic membrane loading on the esterification were investigated by the esterification of dodecanoic acid with methanol. The dodecanoic acid conversion reaches 97.5% trader the optimal condition when the esterification reaction lasted for 8 h.
