Effect of chemically different calcium antagonists on lipid profile in rats fed on a high fat diet.

Different classes of calcium antagonists, viz. verapamil (diphenylalkylamine), diltiazem (benzothiazepine), nifedipine, felodipine and nimodipine (dihydropyridines), were examined for their effects on lipid profile in rats. Clofibrate was the reference standard. Clofibrate significantly prevented the rise of serum triglycerides and total cholesterol produced by high fat diet and raised antiatherogenic index to 1.6 times than that of high fat diet controls. Of the calcium antagonists studied, felodipine was most effective in preventing the rise of serum triglycerides and total cholesterol in high fat diet fed rats. Felodipine's antiatherogenic index was very high (886%)--much more than that of clofibrate (303%). Diltiazem and nimodipine which also significantly prevented the rise in triglycerides and total cholesterol produced by high fat diet had a moderately beneficial antiatherogenic index similar to that of clofibrate. Though verapamil and nifedipine slightly increased the triglyceride levels, total cholesterol levels were reduced only by verapamil and not by nifedipine. Despite this both these drugs moderately raised antiatherogenic index similar to clofibrate.     

Changes in lipid profiles of brain of albino rats following envenomation

Effect of high doses of cobra venom (150 micrograms/120 +/- 20 g body weight) and viper venom (300 micrograms/120 +/- 20 g body weight) on total lipid, triglyceride, phospholipid, cholesterol, high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) of brain of albino rats was studied. Total lipid (TL) triglyceride (TG) and phospholipid (PL) are decreased in both viper and cobra venom treated groups while cholesterol (C), and LDL-C are increased in both the groups in relation to controlled ones. HDL-C content was almost unaltered. Decrease in triglyceride and phospholipid may be due to effect of lipases and phospholipases whereas increased cholesterol and LDL-C may be attributed to lysis of cell membrane.     

P-aminodiphenylamine induced biochemical changes in sex organs of male albino rats.

Intraperitoneal administration of p-aminodiphenylamine (p-ADPA), an aromatic amine of wide industrial applications, / 42.5 mg/kg body weight for 180 days significantly decreased the activities of testicular lactate dehydrogenase and hyaluronidase and lactic acid content indicating arrest of spermatogenesis. Patchy necrosis of the testis was confirmed histopathologically. No change in testicular cholesterol, fructose content of coagulating glands and dorso-lateral prostate and activities of alkaline phosphatase in seminal vesicle and acid phosphatase in ventral prostate support normal androgenic status.     

Changes in UCP expression in tissues of Zucker rats fed diets with different protein content

The effect of dietary protein content on the uncoupling proteins (UCP) 1, 2 and 3 expression in a number of tissues of Zucker lean and obese rats was studied. Thirty-day-old male Zucker lean (Fa/?) and obese (fa/fa) rats were fed on hyperproteic (HP, 30% protein), standard (RD, 17% protein) or hypoproteic (LP, 9% protein) diets ad libitum for 30 days. Although dietary protein intake affected the weights of individual muscles in lean and obese animals, these weights were similar. In contrast, huge differences were observed in brown adipose tissue (BAT) and liver weights. Lean rats fed on the LP diet generally increased UCP expression, whereas the HP group had lower values. Obese animals, HP and LP groups showed higher UCP expression in muscles, with slight differences in BAT and lower values for UCP3 in subcutaneous adipose tissue. The mean values of UCP expression in BAT of obese rats were lower than in their lean counterpart, whereas the expression in skeletal muscle was increased. Thus, expression of UCPs can be modified by dietary protein content, in lean and obese rats. A possible thermogenic function of UCP3 in muscle and WAT in obese rats must be taken into account.     

Diet supplementation with beta-carotene improves the serum lipid profile in rats fed a cholesterol-enriched diet

The present study investigated the underlying mechanism associated with the hypocholesterolemic activity of beta-carotene by examining its effects on the serum lipid profile, fecal cholesterol excretion, and gene expression of the major receptors, enzymes, and transporters involved in cholesterol metabolism. Female Fischer rats were divided into three groups and were fed either a control or a hypercholesterolemic diet supplemented or not supplemented with 0.2 % beta-carotene. After 6 weeks of feeding, blood, livers, and feces were collected for analysis, and quantitative real-time polymerase chain reaction (qRT-PCR) was performed. Dietary supplementation with 0.2 % beta-carotene decreased serum total cholesterol, non-HDL cholesterol, the atherogenic index, and hepatic total lipid and cholesterol contents. These changes were accompanied by an increase in the total lipid and cholesterol contents excreted in the feces. The qRT-PCR analyses demonstrated that the hypercholesterolemic diet promoted a decrease in the gene expression of sterol regulatory element-binding protein 2, 3-hydroxy-3-methylglutaryl CoA reductase, and low-density lipoprotein receptor and an increase in the gene expression of peroxisome proliferator-activated receptor α and cholesterol-7a-hydroxylase. The expression of these genes and gene expression of ATP-binding cassette subfamily G transporters 5and 8 were unaffected by beta-carotene supplementation. In conclusion, the decrease in serum cholesterol and the elevation of fecal cholesterol obtained following beta-carotene administration indicate that this substance may decrease cholesterol absorption in the intestine and increase cholesterol excretion into the feces without a direct effect on the expression of cholesterol metabolism genes.     

The effects of L-carnitine on some hematological parameters in rats fed a cholesterol-rich diet

We evaluated the effects of L-carnitine on the hematological characteristics of rats fed a cholesterol-rich diet. Healthy male Wistar Albino rats were assigned to four equal groups. During the 40 day experiment, group 1 was fed standard rat pellets, group 2 was fed standard rat pellets containing 7.5 % cholesterol powder, group 3 was fed standard rat pellets and water that contained 75 mg/l L-carnitine, and group 4 was fed standard rat pellets that contained 7.5% cholesterol and water that contained 75 mg/l L-carnitine. Blood samples were analyzed for red (RBC) and white (WBC) blood cells, hemoglobin, hematocrit, granulocytes, lymphocytes, monocytes, mean cell volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC) using an automated cell counter. The RBC count in the group that received the 7.5% cholesterol diet was decreased significantly compared to the other groups. The hematocrit of the cholesterol group was lower than for the L-carnitine + cholesterol and L-carnitine groups. The MCV in the cholesterol group was significantly higher than the control group. The MCH in the cholesterol group was higher than for the other groups. There was no significant difference among the groups with regard to hemoglobin, MCHC, WBCs and leukocyte types. L-carnitine appears to have beneficial effects on erythrocyte stability, erythropoiesis and hyperlipidemia.     

Changes in the sugar content of barley anthers during culture on different carbohydrates

The quantity of glucose liberated by an anther homogenate from nine different carbon substrates, was examined to elucidate the rate of carbohydrate breakdown by anther tissues in culture. The possible relationship between these results and development in culture was examined by extraction, and HPLC analysis of the soluble sugars from anthers cultured on medium containing one of four of the previously tested carbon substrates. Similarly, sugars from anthers subjected to one of three different inductive pretreatments, were analysed and compared with extracts from fresh anthers. The most successful carbon source in culture, when measured by fresh, and dry weight gain of the developing anthers, were the diglucoses maltose and cellobiose. Glucose was probably liberated from these diglucose substrates at a similar rate to that at which it could be utilized during the development of microspore derived structures. Pretreatments were shown to increase the glucose content of anthers, providing a pulse of the sugar at the start of culture. This effect was particularly pronounced when anthers were preincubated on a medium containing mannitol, and this type of pretreatment was found to be the most successful in promoting the development of microspore derived structures (measured by gain in fresh and dry weight) when subsequently cultured on medium containing maltose.