Serum constituents of Suncus murinus

Blood samples were collected by cardiac puncture from nine-week-old suncus, mice and rats those had been fasted for 16 hours, and the serum was assayed for the levels of corticosterone, cortisol, and other constituents. The following results were obtained: The serum levels of corticosterone and cortisol and corticosterone/cortisol ratio of suncus were about the same as those of human. The SGPT, gamma-GT, ALP, LDH, Ca and K values in suncus were all within the normal range of the respective values in human. SGOT, amylase, BUN, Na, Cl, Fe and inorganic phosphate values were higher, and total cholesterol, triglyceride, phospholipid, creatinine, urea, total protein, albumin and bilirubin levels were lower in suncus than the respective normal values in human. The values of SGOT, amylase, ZTT, and K were higher in female than in male suncus, while the values of gamma-GT and ALP were higher in the male. Feeding the animals individually in the individual cages for a week increased the values of direct bilirubin, total cholesterol, ZTT, Na, K and Cl and lowered the value of urea. The values of SGPT, ALP and triglyceride of suncus obtained in 1984 were higher, the value of albumin was lower, than the respective values obtained in 1983. The value of cholinesterase in suncus was very small.     

Induction of fatty liver by fasting in suncus

We found that a fatty liver was easily induced in a novel experimental animal, Suncus murinus (suncus), by withholding food. Hepatic triglyceride content increased linearly for up to 24 h after fasting in these animals. Serum levels of neutral lipids are very low in the fed state compared with those in rats, and decreased significantly after 24 h fasting. On the other hand, serum free fatty acids, which are at the same level in fed animals as in rats, increased threefold in the fasting suncus. In order to learn whether the fatty liver induced by fasting is an unusual physiological state or a pathological on-going state in suncus, they were refed after 24 h fasting. Refeeding resulted in a decrease in hepatic triglyceride content to the level of fed animals. Serum lipid levels, which decreased with fasting, returned to those of fed animals. This evidence indicates that hepatic lipid secretion is impaired even in a physiological state to some extent and that starvation causes increasing influx of free fatty acid to the liver, which might be followed by esterification and result in triglyceride accumulation in the liver. In conclusion, hepatic lipid and lipoprotein metabolism is unique to the suncus, which is a useful animal model for the study of intra-hepatic lipid transport.     

Studies on the Fatty Liver Diseases of Sciaenops ocellatus Caused by Different Ether Extract Levels in Diets

An experiment was conducted to study fatty liver disease caused by different ether extract levels in diets of juvenile Sciaenops ocellatus.Juvenile S.ocellatus(n=1,260;initial body weight approximately 2.73 g) were divided into nine treatment groups (triplicate groups per treatment) and fed in aquatic cases by a recirculated filtered rearing system;the temperature of the aquatic cases was maintained at 23.2±2.0°for 8 weeks.Nine kinds of diets containing different protein (38,42,46%) and ether extract levels (4,8,12%) were used.Results showed that the relative growth ratio and survival ratio of the fish fed on medium lipid diets (8%) or high ether extract diets (12%)were significantly lower than those of the fish fed on low ether extract diets (4%) (p<0.05).There was a positive correlation between the ether extract contents in hepatopancreas of fish and the ether extract contents of diets.At the end of the experimental period,the fish of the nine experimental groups suffered from different degrees of fatty liver disease and serious illness,and death occurred in a large number offish fed on medium (8%) and high ether extract diets (12%) from the third test week;mortality was highest in the fifth test week.The ill S.ocellatus showed symptoms of loss of appetite,lack of movement,black skin,and weight loss and eventually died.The main pathological change in ill fish was fatty liver disease.Their hepatopancreas were swollen and pale,accompanied by fatty degeneration,fatty necrosis of hepatocytes,and atrophy of the pancreas.Ultrastructural changes showed the presence of many lipid droplets and granules in the mitochondria,endoplasmic reticulum,and cell plasm of hepatocytes.Study results indicated that all the nine kinds of diets with different lipid or protein levels could cause nutritional fatty liver disease in juvenile S.ocellatus.The pathological severity and serious level of fatty liver disease in the tested fish positively correlated with the contents of the ether extract,but not with those of protein,in test diets.The increase in the level of ether extract in test diets was responsible for the direct cause of illness or death in juvenile S.ocellatus.     

Studies on the Fatty Liver Diseases of Sciaenops ocellatus Caused by Different Ether Extract Levels in Diets

An experiment was conducted to study fatty liver disease caused by different ether extract levels in diets of juvenile Sciaenops ocellatus. Juvenile S. ocellatus (n=1,260; initial body weight approximately 2.73 g) were divided into nine treatment groups (triplicate groups per treatment) and fed in aquatic cases by a recirculated filtered rearing system; the temperature of the aquatic cases was maintained at 23.2±2.0° for 8 weeks. Nine kinds of diets containing different protein (38, 42, 46%) and ether extract levels (4, 8, 12%) were used. Results showed that the relative growth ratio and survival ratio of the fish fed on medium lipid diets (8%) or high ether extract diets (12%) were significantly lower than those of the fish fed on low ether extract diets (4%) (p < 0.05). There was a positive correlation between the ether extract contents in hepatopancreas of fish and the ether extract contents of diets. At the end of the experimental period, the fish of the nine experimental groups suffered from different degrees of fatty liver disease and serious illness, and death occurred in a large number of fish fed on medium (8%) and high ether extract diets (12%) from the third test week; mortality was highest in the fifth test week. The ill S. ocellatus showed symptoms of loss of appetite, lack of movement, black skin, and weight loss and eventually died. The main pathological change in ill fish was fatty liver disease. Their hepatopancreas were swollen and pale, accompanied by fatty degeneration, fatty necrosis of hepatocytes, and atrophy of the pancreas. Ultrastructural changes showed the presence of many lipid droplets and granules in the mitochondria, endoplasmic reticulum, and cell plasm of hepatocytes. Study results indicated that all the nine kinds of diets with different lipid or protein levels could cause nutritional fatty liver disease in juvenile S. ocellatus. The pathological severity and serious level of fatty liver disease in the tested fish positively correlated with the contents of the ether extract, but not with those of protein, in test diets. The increase in the level of ether extract in test diets was responsible for the direct cause of illness or death in juvenile S. ocellatus. Translated from Acta Hydrobiologica Sinica, 2005, 29(1) (in Chinese)     

Length and weight of gastrointestinal tracts of pikas, suncus, millardias, mice and rats

The length and weight of gastrointestinal tracts including contents of ten week old male pikas (Ochotona rufescens rufescens) and suncus (Suncus murinus) were measured and they were investigated and compared with those of millardias, ICR-mice and Wistar-rats. The length from the duodenum to the anus of pikas was much longer and the weight from the stomach to the anus was about 16g per 100g of body weight. The weight of cecum was about 7g per body weight and they were heavier than those of other species. The length from the duodenum to the anus of the suncus was short but the weight of the small intestine plus colon and rectum per body weight did not differ from that of other species. The suncus has no cecum but the weight from the stomach to the anus was almost the same as that of rats.     

Effect of Dahi containing Lactococcus lactis on the progression of diabetes induced by a high-fructose diet in rats

The antidiabetic effect of dahi was observed on high-fructose-induced diabetic rats. The fasting blood glucose, glycosylated haemoglobin, insulin, free fatty acids and triglyceride levels of the dahi fed group animals were significantly lower than those of the control group (p<0.05). The imparity of the glucose tolerance test was also delayed by one week in the dahi-fed animals.     

饵料中不同脂肪水平诱导红姑鱼脂肪肝病的研究

1260尾初始重约为273g的红姑鱼(Sciaenopsocellatus)分为9组,每组3个平行,用9种不同水平蛋白质与脂肪日粮饲养于循环水系统的水泥池网箱内,在水温为232±20℃条件下养殖56d。本实验为饵料中不同脂肪水平诱导红姑鱼脂肪肝病的研究。9种日粮中蛋白质含量分别为:36%,40%,44%;脂肪含量分别为:4%,8%,12%。红姑鱼的各期生长率和存活率随着日粮脂肪含量增加而显著下降,红姑鱼肝胰脏脂肪含量与日粮脂肪水平成正比,各组红姑鱼均发生程度不同的营养性脂肪肝病,其病变程度与日粮脂肪水平成正相关。饲喂脂肪含量分别为8%,12%日粮的红姑鱼从实验3周起开始大量发病死亡,死亡率在5周达到高峰。主要表现为厌食,不游动,皮肤发黑,消瘦直至死亡。解剖见肝胰脏肿大,苍白发黄,柔软易碎。组织学检查发现,各组红姑鱼肝胰脏均见肝细胞不同程度的脂肪变性,溶解坏死,胰腺细胞亦萎缩。电子显微镜观察,在肝细胞线粒体、内质网与细胞浆内有大量微细至大颗粒状的脂滴出现。实验结果表明,饲喂9种不同水平的蛋白质和脂肪日粮的红姑鱼均引起营养性脂肪肝病,其病变程度与日粮脂肪水平成正相关,日粮中脂肪是红姑鱼发病与死亡的直接原因。       

The Effect of Lipid Peroxide on the Lipid and Carbohydrate Metabolism in Rat Liver

Feeding tests were carried out on rats to clarify the mechanisms of fatty liver formation induced by autoxidized methyl linoleate. Lipid peroxides prepared by autoxidation of highly purified methyl linoleate were given orally to rats. Triglyceride and glycogen contents in liver were determined and enzyme activities including triglyceride synthetase and α-glycerophosphate dehydrogenase were also examined. The following results were obtained. 1. Triglyceride accumulation in rat liver fed autoxidized methyl linoleate was observed. 2. Increase in triglyceride content in rat liver was soon followed by the decrease of hepatic glycogen. 3. When rats were starved prior to introduction of autoxidized methyl linoleate, hepatic triglyceride accumulation did not occur. 4. The activities of α-glycerophosphate dehydrogenase and triglyceride synthetase in liver, and those of glutamic oxalacetic transaminase and leucine aminopeptidase in plasma were practically similar among the rats of test groups fed fresh or autoxidized methyl linoleate and the control fed diet without methyl linoleate. 5. The addition of l-carnitine which is a stimulator of fatty acid oxidation retarded the accumulation of the hepatic triglyceride mentioned above.     

Carbohydrate-restricted diet alters the gut microbiota,promotes senescence and shortens the life span in senescence-accelerated prone mice

This study examined the effects of a carbohydrate-restricted diet on aging, brain function, intestinal bacteria and the life span to determine long-term carbohydrate-restriction effects on the aging process in senescence-accelerated prone mice (SAMP8). Three-week-old male SAMP8 were divided into three groups after a week of preliminary feeding. One group was given a controlled diet, while the others fed on high-fat and carbohydrate-restricted diets, respectively. The mice in each group were further divided into two subgroups, of which one was the longevity measurement group. The other groups fed ad libitum until the mice were 50 weeks old. Before the test period termination, passive avoidance test evaluated the learning and memory abilities. Following the test period, serum and various mice organs were obtained and submitted for analysis. The carbohydrate-restricted diet group exhibited significant decrease in the survival rate as compared to the other two diet groups. The passive avoidance test revealed a remarkable decrease in the learning and memory ability of carbohydrate-restricted diet group as compared to the control-diet group. Measurement of lipid peroxide level in tissues displayed a marked increase in the brain and spleen of carbohydrate-restricted diet group than the control-diet and high-fat diet groups. Furthermore, notable serum IL-6 and IL-1β level (inflammation indicators) elevations, decrease in Enterobacteria (with anti-inflammatory action), increase in inflammation-inducing Enterobacteria and lowering of short-chain fatty acids levels in cecum were observed in the carbohydrate-restricted diet group. Hence, carbohydrate-restricted diet was revealed to promote aging and shortening of life in SAMP8.     

Gastric lipolysis in the developing rat. Ontogeny of the lipases active in the stomach

Two nutritional models, an essential fatty acid deficiency model and the feeding of saturated versus unsaturated fats, were used in a feeding study in order to assess the relationship between tissue fatty acid composition and the activities of some membrane-associated enzymes. Purified diets containing 7% hydrogenated coconut oil, 7% corn oil, 10% safflower oil or butter were fed to rats for a total of 49 weeks (1 week of pregnancy, 3 weeks of lactation and 45 weeks post-weaning). Tissue homogenates from submandibular salivary glands and kidneys were analyzed for fatty acid composition of total lipids and phospholipids. Changes in fatty acid patterns typical of essential fatty acid deficiency such as an increase in the levels of 16:1 and 18:1, a decrease in 18:2 and 20:4 and an accumulation of 20:3 omega 9 were observed in salivary glands and kidneys of rats fed the deficient diet. Tissues of rats fed 10% butter also showed fatty acid compositional changes which were somewhat similar to those in essential fatty acid deficiency, but to a lesser degree. The activities of ouabain-sensitive (Na+ + K+)-ATPase were higher in homogenates of salivary glands and kidneys of the deficient rats and those fed butter as compared with their controls. The results suggest a relationship between the double bond index of fatty acids as an indication of membrane lipid fluidity and allosteric modification of (Na+ + K+)-ATPase activity. However, other explanations for the observed changes in (Na+ + K+)-ATPase activity cannot be ruled out. There were no diet-related differences in the activities of gamma-glutamyltranspeptidase or 5'-nucleotidase.     

Aminotransferase activity in the liver and white muscle of Mugil capito fed diets containing different levels of protein and carbohydrate

Four groups of Mugil capito were fed diets with protein and carbohydrate contents changing reciprocally for 121 days. Food consumption changed proportionally to the carbohydrate content of the diet, while final fish growth was similar for all groups of fish. Liver transaminase levels changed significantly with the protein content of the diet. The changes in body transaminase levels were lower in magnitude. The results obtained are compared to those obtained from other fish species and possible reasons for the differences observed are discussed.     

Reduction and subsequent oxidation of a cytochrome b of human neutrophils after stimulation with phorbol myristate acetate.

The level of nerve growth factor-like immunoreactivity in the lower limb muscles, the site where the dystrophic mice are effected, of both normal and dystrophic mice was studied by solid-phase radioimmunoassay. Nerve growth factor-like immunoreactivity levels of the homozygous dystrophic mice were about two times lower than those of the heterozygous dystrophic mice at 10–11 weeks and 7–8 weeks of age. The levels in 4–5 week old homozygous mice were too low for detection and remarkable differences between the homozygous and the heterozygous mice were observed at this age. These differences in the level of nerve growth factor-like immunoreactivity suggest that the factor may have some relation to the disease.     

Effects of structured lipids containing eicosapentaenoic or docosahexaenoic acid and caprylic acid on serum and liver lipid profiles in rats

The physiological activity and effect on lipid metabolism of four types of structured lipids (SLs), that contain caprylic acid (C8) and either eicosapentaenoic (EPA) or docosahesaenoic acid (DHA), were evaluated in male Wistar rats fed experimental diets containing 7% (wt %) of each SL and 3% (wt %) soybean oil for 28 days. Control rats were fed a diet containing 10% (wt %) soybean oil. The relative perirenal adipose tissue weights of rats fed D-8-8 and 8-D-8 diets were significantly lower than those of other groups. We observed significantly lower serum cholesterol concentrations in rats fed SLs than those of control group over experimental period. The serum lipids concentrations in rats fed diets containing SLs were significantly lower P < 0.05) than those of soybean oil group. The fatty acid compositions of WAT did not reflect the structural differences in the triglyceride. These results suggest that the physiological effects of the SLs used in this study were due to the fatty acids rather than the structural specificity. Therefore, further study will be needed to ascertain the most desirable structural configuration.     

The displacement of albumin bound bilirubin by free fatty acids in vivo

Variations in bilirubinaemia in response to alterations of the free fatty acid level was studied in conscious and unstressed Gunn rats. When only one molecule of bilirubin is bound to albumin (without bilirubin overload), no displacement of bilirubin is observed, even if the protein binds as much as 6 molecules of free fatty acids. After overloading with exogenous unconjugated bilirubin, the second site of fixation of bilirubin on albumin is partly occupied; in this situation, a displacement is observed, but only when more than 3.5 molecules of free fatty acids are simultaneously bound to the protein. In vivo, free fatty acids do not spontaneously reach such levels as those responsable for the observed displacement of bilirubin. In the ranges of bilirubin and free fatty acids concentrations likely to be encountered clinically, free fatty acids might not represent an effective agent of displacement for bilirubin, as it is commonly thought.     

Failure of dietary erucic acid to impair oxidative capacity or APT production of rat heart mitochondria isolated under controlled conditions.

1. Male, 8-week old rats were fed Purina Rat Chow for semisynthetic diets containing 20% by weight of rapeseed oil or corn oil for 3 days. 2. The hearts from the animals fed the three diets were analyzed for total lipid, phospholipid, free fatty acids, cholesterol esters, tri-, di- and monoacylglyerols. There was a seven-fold increase in the levels of triacylglycerols in the hearts of rats fed rapeseed oil diet compared to the levels in the hearts of animals fed the other two diets. Smaller increases in the content of other neutral lipid fractions were also observed. 3. Heart mitochondria from the three groups of animals were isolated under controlled conditions in the presence or absence of heparin. The rats of oxidation of different substrates and of ATP synthesis by these mitochondria were compared. 4. Mitochondria isolated in the absence of heparin from rapeseed oil-fed rats had much lower rates of oxidation and ATP synthesis than mitochondria isolated similarly from rats fed the other two diets. 5. With mitochondria freshly isolated in the presence of heparin, no significant differences in rates of oxidation or ATP synthesis were found among the three groups of animals. 6. It is concluded that, when properly isolated, mitochondria from rapeseed oil-fed rats are functionally intact with respect to oxidation and energy-coupling capacity.     

Failure of dietary erucic acid to impair oxidative capacity or ATP production of rat heart mitochondria isolated under controlled conditions

1. Male, 8-week old rats were fed Purina Rat Chow or semi-synthetic diets containing 20% by weight of rapeseed oil or corn oil for 3 days.2. The hearts from the animals fed the three diets were analyzed for total lipid, phospholipid, free fatty acids, cholesterol esters, tri-, di- and monoacylglycerols. There was a seven-fold increase in the levels of triacylglycerols in the hearts of rats fed rapeseed oil diet compared to the levels in the hearts of animals fed the other two diets. Smaller increases in the content of other neutral lipid fractions were also observed.3. Heart mitochondria from the three groups of animals were isolated under controlled conditions in the presence or absence of heparin. The rates of oxidation of different substrates and of ATP synthesis by these mitochondria were compared.4. Mitochondria isolated in the absence of heparin from rapeseed oil-fed rats had much lower rates of oxidation and ATP synthesis than mitochondria isolated similarly from rats fed the other two diets.5. With mitochondria freshly isolated in the presence of heparin, no significant differences in rates of oxidation or ATP synthesis were found among the three groups of animals.6. It is concluded that, when properly isolated, mitochondria from rapeseed oil-fed rats are functionally intact with respect to oxidation and energy-coupling capacity.     

非酒精性脂肪肝病大鼠肝脏SOCS-3的表达与吡格列酮干预研究

目的：探讨SOCS-3在非酒精性脂肪肝病（NAFLD）发病中的作用以及吡格列酮的干预作用。方法：29只雄性SD大鼠随机分为正常对照组（8只）,高脂饮食组（21只）。饲养8周后,从高质饮食组随机抽取5只大鼠证实造模成功后,将该组余下的16只大鼠继续以高脂饲料喂养,并随机分为NAFLD对照组（8只）;吡格酮干预组（8只）,予以吡格列酮3mg·kg^-1·d^-1灌胃。16周末,处死所有大鼠,检测血糖、血胰岛素、血脂、肝脏SOCS-3mRNA和SREBP-lcmRNA表达及肝脏病理学。结果：与正常对照组相比,NAFLD组血糖、血胰岛素、血脂、肝脏脂肪变水平及肝组织SOCS-3mRNA、SREBPlCmRNA表达显著上调。吡格列酮干预组sOCS．3mRNA、SREBP-1cmRNA表达较NAFLD组下调,且血糖、血胰岛素、血脂、肝脏脂肪变水平下降。SOCS-3mRNA表达水平与胰岛素抵抗指数、SREBP．1cmRNA表达水平、肝脂肪变成显著正相关。结论：SOCS-3可能通过胰岛素抵抗及上调肝组织SREBP-lcmRNA表达参与NAFLD发病,吡格列酮能抑制肝脏SOCS-3的表达,对NAFLD有一定治疗作用。     

Lipid and fatty acid composition of muscle and liver from wild and captive mature female broodstocks of white seabream, Diplodus sargus

Total lipids (TL), lipid classes, and their associated fatty acids from muscle and liver of captive and wild mature female broodstocks were investigated in order to estimate the fatty acid requirements of white seabream (Diplodus sargus). The results showed that the percentage of triacylglycerol was higher in liver and muscle of captive fish than in wild fish. The distribution of phospholipid classes in liver and muscle of both fish groups was similar, phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol being the predominant lipid classes. The general pattern of fatty acid distribution in total lipid of liver and muscle from captive and wild fish was similar. However, the relative percentage of specific fatty acids differed in captive and wild fish. The most noteworthy difference was the lower proportion of arachidonic acid (20:4n-6, AA) and the higher proportion of eicosapentaenoic acid (20:5n-3, EPA) in liver and muscle of captive fish with respect to those of wild fish. The proportion of docosahexaenoic acid (22:6n-3, DHA) did not differ between the two fish groups. The differences in EPA and AA proportions between captive and wild fish implied that captive fish presented a higher EPA/AA ratio and a lower DHA/EPA ratio than wild fish. In general terms, in both liver and muscle, the differences in fatty acid composition observed for TL were extended to all lipid classes. The results suggest that the different AA, EPA and DHA proportions in liver and muscle between captive and wild broodstocks are attributed to different levels of these fatty acids in broodstock diets.     

L-carnitine increases liver alpha-tocopherol and lowers liver and plasma triglycerides in aging ovariectomized rats

The objective of this study was to determine whether dietary L-carnitine can influence the status of alpha-tocopherol, retinol and selected lipid parameters in aging ovariectomized rats, an animal model for the menopausal state. Fourteen Fisher-344 female rats 18 months old were acclimated for 4 weeks and ovarectomized. Seven rats per treatment were assigned to either a control group fed ad libitum AIN-93M diet or a carnitine group fed the same diet supplemented with L-carnitine. After an 8-week feeding period, blood and selected tissues were taken for analyses. No differences were noted in food intake, body weight, or organ weights due to L-carnitine. Dietary carnitine significantly increased liver alpha-tocopherol and tended to increase plasma alpha-tocopherol (P<.09). No changes in alpha-tocopherol were observed in other tissues including the brain, lungs and retroperitoneal fat. Retinol levels in plasma and tissues were not affected by supplemental L-carnitine. Significant decreases in liver and plasma triglyceride (TG) levels were noted, suggesting increased utilization of fatty acids. No differences were observed in the fatty acid profile of tissues. The results provide evidence that dietary supplementation of L-carnitine enhances the alpha-tocopherol status and improves the utilization of fat leading to lowering of the liver and plasma levels of TG in aging ovariectomized rats. Whether supplemental L-carnitine may be of benefit to postmenopausal women in lowering plasma TG and improving the antioxidant status remains to be studied.