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1.
The sarcoplasmic reticulum was isolated and characterized in the pure form from normal caprine (Capra hircus) hearts. Under ischemic condition, fatty acids like palmitic acid, palmitoyl carnitine and oleic acid accumulatein vivo. These are known to have a detrimental effect on membrane components. The effects of simulated ischemia on the Ca2+-ATPase were studied using these fatty acidsin vitro at concentrations at which they occurin vivo in the ischemic heart. All three fatty acids inhibited Ca2+-ATPase activity. At lower concentrations, palmitoyl carnitine was the most potent, followed by oleic acid while palmitic acid displayed the least potency. Electron microscopy studies with fatty acids showed morphological disruptions in SR vesicles. The decline in Ca2+-ATPase activity could be attributed to the change in membrane morphology.  相似文献   

2.
The cardiac sarcolemma was characterized in 13 normal and 11 ischemic dog hearts by enzyme analysis and compositional assays. Significant decreases in the activities of the sodium-potassium and calcium pumps and structural compositional disturbances were observed in ischemia. High concentrations of oleic acid, a fatty acid and palmitoyl carnitine, a fatty acid intermediate caused inhibition of the enzyme pump activities of the normal sarcolemma. Thus, ischemia results in the functional impairment of the sarcolemma. Accumulation of fatty acid and fatty acid intermediates, occurring in myocardial ischemia, could be an underlying mechanism.  相似文献   

3.
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4.
The levels of cytotoxic aldehydic products in different culinary oils, with or without thermal stress, (routine domestic or commercial frying) were determined by thiobarbituric acid method. The results showed that (i) thiobarbituric acid reactivity was much higher in edible oils rich in polyunsaturated fatty acids than those rich in saturated fatty acids or monounsaturated fatty acids, even without thermal stress, (ii) the lipid peroxide levels were in proportion to the duration of thermal stress, (iii) nature of the container used (steel, iron or teflon-coated) had no significant effect on the extent of lipid peroxidation under identical conditions of thermal stress and (iv) thermally stressed oils collected from hotels and roadside caterers contained higher levels of cytotoxic aldehydic products, when compared to oils thermally stressed under domestic frying conditions. These results suggest that dietary ingestion of thermally or autoxidatively stressed polyunsaturated fatty acid rich culinary oils is more harmful compared with those similarly treated oils rich in saturated fatty acids and monounsaturated fatty acids.  相似文献   

5.
The beneficial effects of ∈-3 fatty acids on human health have been well documented. Fish and fish oils are the richest sources of ∈-3 fatty acids. However, due to their high degree of unsaturation, they are highly susceptible to lipid peroxidation. Regular consumption of peroxidised oils may represent a risk factor for the induction and development of atherosclerosis. In view of the above reports, it was considered necessary to study the effects of tumeric on fish lipid peroxidation during standard cooking practices and on time-dependent changes in the peroxidation of fish homogenate. The antioxidant effect of α-tocopherol was also studied to confirm the relevance of the study. The results suggest that turmeric may be considered as a safe, cheap and readily usable antioxidant for food preparations.  相似文献   

6.
Short-chain acyl-CoA dehydrogenase (ACAD) deficiency is an extremely rare inherited mitochondrial disorder of fat metabolism. This belongs to a group of diseases known as fatty acid oxidation disorders. Screening programmes have provided evidence that all the fatty acid oxidation disorders combined are among the most common inborn errors of metabolism. Mitochondrial beta oxidation of fatty acids is an essential energy producing pathway. It is a particularly important pathway during prolonged periods of starvation and during periods of reduced caloric intake due to gastrointestinal illness or increased energy expenditure during febrile illness. The most common presentation is an acute episode of life threatening coma and hypoglycemia induced by a period of fasting due to defective hepatic ketogenesis. Here, the case of a 4 month old female patient who had seizures since the third day of her birth and persistent hypoglycemia is described. She was born to parents of second degree consanguinity after 10 years of infertility treatment. There was history of delayed cry after birth. Metabolic screening for TSH, galactosemia, 17-OHP, G6PD, cystic fibrosis, biotinidase were normal. Tandem mass spectrometric (TMS) screening for blood amino acids, organic acids, fatty acids showed elevated butyryl carnitine (C4) as 3.40 μmol/L (normal <2.00 μmol/L), hexanoyl carnitine (C6) as 0.92 μmol/L (normal <0.72 μmol/L), C4/C3 as 2.93 μmol/L (normal <1.18 μmol/L). The child was started immediately on carnitor syrup (carnitine) 1/2 ml twice daily. Limitation of fasting stress and dietary fat was advised. Baby responded well by gaining weight and seizures were controlled. Until now, less than 25 patients have been reported worldwide. The limited number of patients diagnosed until now is due to the rarity of the disorder resulting in under diagnosis.  相似文献   

7.
The antidyslipidemic activity of Ocimum sanctum leaf extract was studied in streptozotocin induced diabetic rats. In this model, there was significant increase in plasma markers of diabetic-dyslipidemia following diminution of lipid metabolizing enzymes. Oral administration of leaf extract (500 mg/kg b.w.p.o.) for 15 days resulted in significant decrease in diabetogenic and dyslipidemia parameters; namely blood glucose, glycosylated hemoglobin, lipid peroxide, free fatty acids, small dense low density lipoprotein, lipid and protein components of plasma lipoproteins, adipose and liver. The regulation of lipids was accompanied by stimulation of postheparin lipolytic activity, reactivation of lecithin cholesterol acyl transferase and hepatic lipoprotein lipase enzymes. The results of the present study demonstrated antidyslipidemic and antioxidant activities in leaf extract of O. sanctum which could be used in prevention of diabetic-dyslipidemia and related complications.  相似文献   

8.
Chemical composition of gall stones is essential for aetiopathogensis of gallstone disease. We have reported quantitative chemical analysis of total cholesterol bilirubin, calcium, iron and inorganic phosphate in 120 gallstones from haryana. To extend this chemical analysis of gall stones by studying more cases and by analyzing more chemical constituents. A quantitative chemical analysis of total cholesterol, total bilirubin, fatty acids, triglycerides, phospholipids, bile acids, soluble proteins, sodium potassium, magnesium, copper, oxalate and chlorides of biliary calculi (52 cholesterol, 76 mixed and 72 pigment) retrieved from surgical operation of 200 patients from Haryana state was carried out. Total cholesterol as the major component and total bilirubin, phospholipids, triglycerides, bile acids, fatty acids (esterified), soluble protein, calcium, magnesium, iron, copper, sodium, potassium, inorganic phosphate, oxalate and chloride as minor components were found in all types of calculi. The cholesterol stones had higher content of total cholesterol, phospholipids, fatty acids (esterified), inorganic phosphate and copper compared to mixed and pigment stones. The mixed stones had higher content of iron and triglycerides than to cholesterol and pigment stones. The pigment stones were richer in total bilirubin, bile acids, calcium, oxalate, magnesium, sodium, potassium, chloride and soluble protein compared to cholesterol and mixed stones. Although total cholesterol was a major component of cholesterol, mixed and pigment gall stone in Haryana, the content of most of the other lipids, cations and anions was different in different gall stones indicating their different mechanism of formation.  相似文献   

9.
Fish and fish oils are the richest sources of ω-3 fatty acids. However, they are susceptible to lipid peroxidation due to their high degree of unsaturation. In the present study, the level of thiobarbituric acid reactive material in various fish oils available in the market with and without added Vitamin E was determined. The peroxide levels in fish oil heated to food frying temperature of 180°C and the effect of addition of vitamin E has also been studied. The results indicate that the peroxide levels in almost all the products available in the market were abnormally high irrespective of their Vitamin E content. This might be due to the inefficient methods used for processing and storage of fish oils. Addition of vitamin E was found to have a significant effect in lowering the rate of peroxidation of fish oil during thermal stress, showing that association of antioxidants with ω-3 fatty acids lowers the rate of lipid peroxidation.  相似文献   

10.
The excessive generation of reactive oxygen species (ROS) by abnormal spermatozoa and contaminating leukocytes has been defined as one of the few etiologies for male infertility. Administration of antioxidants in patients with ‘male factor’ infertility has begun to attract considerable interest. The main difficulty of such an approach is our incomplete understanding of the role of free radicals in normal and abnormal sperm function leading to male infertility. Mammalian spermatozoa membranes are very sensitive to free radical induced damage mediated by lipid peroxidation, as they are rich in polyunsaturated fatty acids. Limited endogenous mechanisms exist to reverse these damages. ROS attacks the fluidity of the sperm plasma membrane and the integrity of DNA in the sperm nucleus. ROS induced DNA damage accelerate the germ cell apoptosis. Unfortunately spermatozoa are unable to repair the damage induced by excessive ROS as they lack the cytoplasmic enzymes required to accomplish the repair. Assessment of such oxidative stress status (OSS) may help in the medical treatment. Treatment strategies must be directed toward lowering of ROS levels to keep only a small amount necessary to maintain normal cell function.  相似文献   

11.
This paper deals with the constituents of fatty acids from the seed oils of Pinaceae in China, including 30 species belonging to 8 genera.  Discovered are three characteristic fatty acids, i.e. Cis-5,9-octadecadienoic acid, Cis-5,9,12-octadecatrienoic acid and Cis-5, 11, 14-eicosatrienoic acid. Based on the data obtained, the distribution of the three characteristic fatty acids in Pinaceae of China is also discussed.  相似文献   

12.
天仙子籽油中脂肪酸组成的研究   总被引：4，自引：0，他引：4  
孙刚 《青海科技》2000,7(1):24-25
采用气相色谱法对天仙子籽油中脂肪酸的组成及相对含量进行了研究。鉴定了油酸、亚油酸等十种脂肪酸、其中油酸含量为１６．３２％,亚油酸含量高达７４．８１％。  相似文献   

13.
Colorectal cancer is one of the most common malignancies and is the second leading cause of cancer death worldwide. Generally, there are three categories of colorectal cancer development mechanism—genetic, epigenetic and aberrant immunological signaling pathways—all of which may be initiated by an imbalanced gut microbiota. Epigenetic modifications enable host cells to change gene expression without modifying the gene sequence. The microbiota can interact with the host genome dynamically through the interface presented by epigenetic modifications. In particular, bacterially derived short-chain fatty acids have been identified as one clear link in the interaction of the microbiota with host epigenetic pathways. This review discusses recent findings relating to the cross talk between the microbiota and epigenetic modifications in colorectal cancer.  相似文献   

14.
Docosahexaenoic (DHA) and arachidonic acids (AA) are polyunsaturated fatty acids (PUFAs), major components of brain tissue and neural systems, and the precursors of a number of biologically active metabolites with functions in inflammation resolution, neuroprotection and other actions. As PUFAs are highly susceptible to peroxidation, we hypothesised whether cigarette smokers would present altered PUFAs levels in plasma and erythrocyte phospholipids. Adult males from Indian, Sri-Lankan or Bangladeshi genetic backgrounds who reported smoking between 20 and 60 cigarettes per week were recruited. The control group consisted of matched non-smokers. A blood sample was taken, plasma and erythrocyte total lipids were extracted, phospholipids were separated by thin layer chromatography, and the fatty acid content analysed by gas chromatography. In smokers, dihomo-gamma-linolenic acid, the AA precursor, was significantly reduced in plasma and erythrocyte phosphatidylcholine. AA and DHA were significantly reduced in erythrocyte sphingomyelin. Relatively short term smoking has affected the fatty acid composition of plasma and erythrocyte phospholipids with functions in neural tissue composition, cell signalling, cell growth, intracellular trafficking, neuroprotection and inflammation, in a relatively young population. As lipid peroxidation is pivotal in the pathogenesis of atherosclerosis and neurodegenerative diseases such as Alzheimer disease, early effects of smoking may be relevant for the development of such conditions.  相似文献   

15.
 22 kinds of seed oils were extracted from 8 genera of the family Ulmaceae in China The seed oils were examined for their characteristics and fatty acid compositions by gas liquid chromatography.  The fatty acid compositions of these oils were found to fall into two classes. Some genera (such as  Ulmus,  Zelkova)  contain  mainly lower saturated acids, in which the chief acid is capric acid 10:0, while the genera (such as Celtis, Pteroceltis, Aphananthe, Trema, Gironniera) contain mainly unsaturat- ed acids, in which the chief acid is linoleic acid  18:2.  Hemiptelea  davidii  (Hance) Planch contain however either certain amount of short-chain saturated acids or higher unsaturated acids, it appears a intermediate genus between the two classes.  According to the component acids we support that the Ulmaceae be split into two subfamilies. The genera arrangement based on the component acids corresponds basically with the view based on mophological characters and flavonoids found in leaves of Ulmaceae, but there are some discrepancies in certain genera, for example, the Aphananthe should beplaced in Celtoid instead of Ulmoid by the present study.  相似文献   

16.
Early identification of patients with acute myocardial infarction is of prime importance due to the associated very high mortality. Only 22% of the patients presenting at emergency cardiology care with chest pain have coronary disease. A number of biochemical tests like CKMB and Troponin-T/I have been introduced for early detection of the coronary syndrome (ACS). Ischemia modified albumin (IMA) has been recently introduced as a marker of myocardial ischemia. We estimated serum IMA in four sequential samples from 25 patients admitted to ICCU. Twenty five healthy volunteers formed the control group from which the normal range was derived. IMA was significantly raised in ischemia patients than in controls as well as compared to the patients who did not have cardiac ischemia. IMA demonstrated good discrimination between the ischemic and the non-ischemic patients with an Odds Ratio of 16.9 (6.29–46.87) than CKMB which showed an Odds Ratio of 2.07 (1.18–6.08). Sensitivity and specificity of IMA for the detection of ACS was 78.0% and 82.7% compared to 58.0% and 60.0%, respectively for the CK-MB assay. The area under the ROC curve of IMA for ischemic v/s non-ischemic patients was 0.834. IMA appears to be developing into a new and very potent marker, of cardiac ischemia.  相似文献   

17.
Membrane lipid and protein composition was compared in erythrocytes from iron deficiency anemia (IDA) and heterozygous beta thalassemia patients. The study was planned to correlate the influence of iron deficiency with the intrinsic defect of the heterozygous condition on the membrane structural integrity as well as to investigate whether there are differences in membrane changes between the two conditions. Results indicate high levels of saturated fatty acids and low unsaturated fatty acids in both disorders although arachidonic acid and the unsaturation index were lower in heterozygous thalassemia than IDA. Nevertheless, neither of the conditions provoked any alterations in membrane protein or glycophorin suggesting alterations in the lipid moiety only. Present findings indicate that irrespective to the etiology, both, iron deficiency and the heterozygous condition show a common pattern of lipid derangement, which may in turn result in increased membrane rigidity and decreased cellular deformability.  相似文献   

18.
The effect of acute hypoxic hypoxia on the profile of plasma amino acids in rats was studied and compared to that resulting from acute liver injury induced by giving carbon tetrachloride. In hypoxic rats exposed to 45% air in N2 for 5 h, the concentrations of branched chain amino acids, including valine, leucine and isoleucine, and aromatic amino acids such as phenylalanine and tyrosine were significantly increased as compared to those in normoxic rats. The ratio of branched-chain to aromatic amino acids (Fischer’s ratio) was significantly decreased. The levels of arginine and citrulline, which are related to the urea cycle, were also depressed. Furthermore, plasma proline level was reduced in hypoxic rats. The activities of plasma marker enzymes for tissue damage remained unchanged during hypoxia, indicating that tissue injury was not induced by exposure to hypoxic conditions. We suggest that the characteristic profile of plasma amino acids and the Fischer ratio are valuable tools for understanding the pathology of acute hypoxia in the absence of systemic tissue damage.  相似文献   

19.
长期施肥对农田黑土微生物群落的影响   总被引：1，自引：0，他引：1  
研究不同磷肥处理农田黑土基本理化性质、磷脂脂肪酸、酸（碱）性磷酸酶、微生物量碳或氮等变化规律。结果表明,有机肥-化肥配施明显提高土壤有机质、总氮以及速效氮、磷、钾等养分含量,进而促进微生物量碳、微生物量碳/有机质比值、磷酸酶活力以及各菌群磷脂脂肪酸含量显著增加。长期氮磷钾配施土壤有机质活性严重退化、不利于土壤微生物生长,而单施磷肥或氮磷肥配施对微生物活力与结构影响较小。有机肥处理中单烯不饱和/饱和脂肪酸比值>1,远高于其他化肥处理,可用来指示有机质质量与可用性;而支链/单烯不饱和脂肪酸与单烯不饱和/饱和脂肪酸比值呈极显著负相关,表明G+菌对养分胁迫抗性强于G-菌。磷脂脂肪酸PCA表明,有机肥与化肥处理微生物群落结构显著不同。个别脂肪酸载荷值分析表明,真菌受无机肥施用影响显著;而G+菌更易受有机肥影响。  相似文献   

20.
豆科七种野生植物籽油脂肪酸研究   总被引：1，自引：0，他引：1  
采用毛细管气相色谱法,对青海境内的豆科七个属的七种野生植物种子的含油率,理化常数和脂肪酸组成及相对含量进行了测定,结查表明,所测植物籽油中,主要为棕榈酸,硬脂酸,油酸,亚油酸和亚麻酸。  相似文献   

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