Effect of Aloe vera (L.) Burm. fil. leaf gel and pulp extracts on kidney in type-II diabetic rat models

Significant degenerative changes were observed in the kidney tissue of untreated neonatal streptozotocin (n0STZ)-induced type-II diabetic rats. These degenerative changes were diminished in the kidney tissue of diabetic animals given glibenclamide and Aloe leaf gel and pulp extracts. Kidney lipid peroxidation levels were increased in diabetic rats compared to healthy rats; these levels were higher in rats treated with glibenclamide than in those which received Aloe extracts. Serum urea and creatinine levels were higher in diabetic rats in comparison to healthy rats. The administration of Aloe gel extract and glibenclamide decreased serum urea and creatinine levels in comparison to diabetic controls. Only A. vera leaf gel extract showed improvement both in histological and biochemical parameters suggesting a protective effect of A. vera on mild damage caused by type-II diabetes on kidney tissue.     

Efficacy of piperine, an alkaloidal constituent from Piper nigrum on erythrocyte antioxidant status in high fat diet and antithyroid drug induced hyperlipidemic rats

The main aim of this study was to investigate the effect of piperine on erythrocyte antioxidant status in high fat diet (HFD) and antithyroid drug induced hyperlipidemic rats. Male Wistar rats were divided into eight groups. The first four groups were fed a control diet and in addition were given respectively 1% carboxymethyl cellulose (CMC); 10 mg/kg body weight carbimazole (CM); 10 mg CM + 40 mg/kg body weight piperine and 10 mg CM + 2 mg/kg body weight atorvastatin (ATV). A similar pattern was followed for the next four groups except that they were all fed HFD instead of the control diet. Erythrocyte osmotic fragility, total cholesterol, phospholipids, lipid peroxidation products, enzymic and non-enzymic antioxidant status were studied in all experimental groups. Significantly increased osmotic fragility, total cholesterol/phospholipid ratio, thiobarbituric acid reactive substances and lipid hydroperoxides were observed in the plasma and erythrocytes of HFD fed and CM treated rats compared to the control. Superoxide dismutase, catalase, glutathione peroxidase, vitamin E and reduced glutathione in erythrocytes and vitamin C in the plasma were also significantly lowered in HFD fed, antithyroid drug treated rats compared to control animals. Concurrent piperine supplementation along with HFD and antithyroid drug administration normalized erythrocyte osmotic fragility, reduced lipid peroxidation, and improved the enzymic and non-enzymic antioxidant status compared to those rats that did not receive piperine. Thus, our results indicate that piperine supplementation markedly protects erythrocytes from oxidative stress by improving the antioxidant status in HFD fed antithyroid drug treated rats.     

A comparative study of the effects of topical application of Aloe vera, thyroid hormone and silver sulfadiazine on skin wounds in Wistar rats

Many research studies report the healing effects of Aloe Vera, thyroid hormone cream and silver sulfadiazine. However, the effects of these therapeutic agents are not well understood and have not been compared in one study. This study aimed at investigating the effects of topical application of an Aloe vera gel, a thyroid hormone cream and a silver sulfadiazine cream on the healing of skin wounds surgically induced in Wistar rats for determining the treatment of choice. In a randomized controlled trial, twelve male rats, aged 120 days and with a mean weight of 250 to 300 g, were divided randomly into 5 groups based on drug treatments: Aloe vera gel (AV), thyroid hormone cream (TC), silver sulfadiazine 1% (S), vehicle (V) and control. To evaluate the efficacy of each treatment technique, a biomechanical approach was used to assess tensile stress after 14 days of treatment. Tensile stress was significantly improved in the Aloe vera gel group as compared with the other four groups (P≤0.05). While the other treatment options resulted in better healing than the control group, this difference was not significant. We conclude that Aloe vera topical application accelerated the healing process more than thyroid hormone, silver sulfadiazine and vehicle in surgically induced incisions in rats.     

Lithium-Induced Hypothyroidism: Oxidative Stress and Osmotic Fragility Status in Rats

The present study was conducted to explore the possible effects of different doses of lithium carbonate on thyroid functions, erythrocyte oxidant–antioxidant status, and osmotic fragility. Twenty-four Wistar-type male rats were equally divided into three groups: groups I and II received 0.1 and0.2 % lithium carbonate in their drinking water, respectively, for 30 days. The rats in group III served as controls, drinking tap water without added lithium. At the end of the experimental period, the erythrocyte osmotic fragility and the levels of triiodothyronine (T₃), thyroxine (T₄), thyroid-stimulating hormone (TSH), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH) were measured in blood samples. Compared to controls, there was a statistically significant increase of TSH but decreases of the T₃ and T₄ levels in group II. Both experimental groups showed a statistically significant increase of the maximum osmotic fragility limit. The minimum osmotic fragility values of the animals in group II were statistically higher than those of controls. The standard hemolytic increment curve of both experimental groups was shifted to the right when compared to the curve obtained from the controls. Also, relative to controls, the activities of MDA and SOD were significantly higher and the GSH level lower in group II, but not so in group I. The results of the present study show that treatment with lithium carbonate may result in thyroid function abnormalities, increased oxidative damage, and possible compromise of the erythrocyte membrane integrity resulting from increased osmotic fragility.     

Effect of Aloe vera gel extract on antioxidant enzymes and azoxymethane-induced oxidative stress in rats

The present work was undertaken with a view to study the effect of oral feeding of 2% Aloe vera gel extract (AGE) for 30 days on azoxymethane (AOM)-induced oxidative stress in rats. It was observed that AOM administration resulted in a significant increase in malondialdehyde and conjugated dienes, with reduction in hepatic glutathione (GSH), vitamin A and uric acid contents. AOM-induced reduction in hepatic GSH and uric acid was brought back to normal by AGE. There was a significant raise in hepatic catalase, superoxide dismutase and glucose-6-phosphate dehydrogenase (G-6-PD) activities as a result of feeding of the extract. Ingestion of the extract effected reduction in AOM-induced colonic GSH-peroxidase, G-6-PD and glutathione S-transferase and femur bone marrow micronuclei formation. Hence, it is suggested that Aloe vera gel extract possess the ability to reduce AOM- induced oxidative stress and toxicity in liver.     

Betaine prevents loss of sialic acid residues and peroxidative injury of erythrocyte membrane in ethanol-given rats

To evaluate chronic ethanol toxicity on erythrocyte membrane and preventive action of betaine as a methyl donor, 24 male Wistar albino rats were divided into three groups: control, ethanol and ethanol plus betaine group. Animals were fed 60 ml diet per day for two months. Rats in the ethanol group were fed ethanol 8 g/kg/day. The ethanol + betaine groups were fed ethanol plus betaine (0.5% w/v). After two months, all animals were killed. Malondialdehyde (MDA) and sialic acid (SA) levels were determined in plasma samples. Osmotic fragility tests were performed on whole blood samples and erythrocyte membrane thiol contents were determined using membrane suspensions. Plasma MDA levels in ethanol-given rats were increased significantly compared to the control group of rats (p < 0.05). MDA in the betaine group was significantly lower than that in the ethanol group (p < 0.05). Erythrocyte membrane thiol contents in ethanol group were decreased compared with those of the control group (p < 0.05). Thiol contents were increased slightly after betaine therapy, but this increase was not statistically significant (p > 0.05). Plasma sialic acid levels in the ethanol group were significantly higher than in the control group (p < 0.05). Sialic acid was decreased in the betaine group compared to the ethanol group (p < 0.05). In the osmotic fragility test, we observed that chronic ethanol consumption increased erythrocyte hemolysis. Betaine protected against ethanol-induced hemolysis. Our findings show that chronic ethanol administration affects erythrocyte membrane properties and this may be related to oxidative stress. Betaine protects erythrocyte membrane alterations against chronic ethanol toxicity. Therefore betaine as a nutritional agent, may protect ethanol induced clinical problems associated with membrane abnormalities.     

Exercise-induced oxidative stress affects erythrocytes in sedentary rats but not exercise-trained rats.

Oxidant stress is one of the factors proposed to be responsible for damaged erythrocytes observed during and after exercise. The impact of exertional oxidant stress after acute exhaustive treadmill running on erythrocyte damage was investigated in sedentary (Sed) and exercise-trained (ET) rats treated with or without antioxidant vitamins C and E. Exhaustive exercise led to statistically significant increments in the levels of thiobarbituric acid-reactive substance (TBARS) and H2O2-induced TBARS in Sed rats and resulted in functional and structural alterations in erythrocytes (plasma hemoglobin concentrations, methemoglobin levels, and rise in osmotic fragility of erythrocytes with decrease in erythrocyte deformability). Administration of antioxidant vitamin for 1 mo before exhaustive exercises prevented lipid peroxidation (TBARS, H2O2-induced TBARS) in Sed rats without any functional or structural alterations in erythrocytes. Parameters indicating erythrocyte lipid peroxidation and deterioration after exhaustive exercise in rats trained regularly with treadmill running for 1 mo were not different from those in Sed controls. Erythrocyte lipid peroxidation (TBARS) increased in exhausted-ET rats compared with ET controls; however, the plasma hemoglobin, methemoglobin levels, and erythrocyte osmotic fragility and deformability did not differ. Exhaustive exercise-induced lipid peroxidation in ET rats on antioxidant vitamin treatment was prevented, whereas functional and structural parameters of erythrocytes were not different from those of the ET controls. We conclude that exertional oxidant stress contributed to erythrocyte deterioration due to exercise in Sed but not in ET rats.     

Effect of acetaminophen toxicity on erythrocyte osmotic fragility in the Fisher rat

The protective effect of propylthiouracil (PTU) pretreatment against acetaminophen-induced erythrocyte osmotic fragility was determined in the male Fisher rat. Hepatotoxicity was assessed for comparative purposes. PTU (0.15%) was fed in chow for a period of 12 days. Acetaminophen (1 g/kg body wt) was then administered orally by a stomach tube after an overnight fast. The rats were killed either 4 or 24 hr later. Erythrocyte osmotic fragility was determined by the extent of hemolysis in various concentrations of NaCl solutions. Hepatotoxicity was assessed by a rise in serum transaminases and by histological examination of hepatic tissue. PTU treatment when compared with control not only protected rats against acetaminophen-induced hepatotoxicity as reported before, but also protected against erythrocyte osmotic fragility. The time course of acetaminophen toxicity seems to be similar for liver and erythrocyte since both showed damage after 24 hr but not after 4 hr of acetaminophen administration. The data show that PTU pretreatment affords protection against acetaminophen-induced increased erythrocyte osmotic fragility even when their glutathione concentrations were not significantly different, suggesting that PTU per se has a protective effect.     

Effects of aqueous extract of kola nut (cola nitida rubra) on reproductive hormones in rats

Our previous study suggests that aqueous extract of kola nut had effect on reproductive hormones in male rats. This study evaluates the effects of kola nut extract on plasma level of testosterone and luteinizing hormones in male rats. 30 adult male rats were used. These were divided into three groups: group A served as control and it received water only, group B and C received kola nut extract only (8mg/kg body weight), C served as recovery group. All the groups were treated for four weeks. The C which served as recovery group was allowed to recover for another four weeks at the end of the extract administration period. The plasma level of testosterone was significantly increased while that of luteinizing hormone was significantly decreased when compared with control animals. The recovery group showed values that were insignificantly lowered but a bit closer to those of the control animals. This showed that the rats were able to recover to some extent after the extract administration.Keywords: Kola nut, Testosterone, Luteinizing hormone, Rat.     

Amelioration of carbon tetrachloride-induced hepatotoxicity and haemotoxicity by aqueous leaf extract of Cnidoscolus aconitifolius in rats

This study was conducted to explore possible protective effect ofCnidoscolus aconitifolius (CA) leaf extract on carbon tetrachloride (CCl4)-induced hepatotoxicity and haemotoxicity in experimental animal models. Thirty six rats of six per group were used in this study. Group I received 10ml/kg normal saline as control. Group II-VI rats were administered with 1.25ml/kg body weight (bwt) of carbon tetrachloride intraperitonealy. Animals in groups III, IV, V and VI were however pre-treated with aqueous extract of Cnidoscolus aconitifolius at 100, 250, 500 and 750mg/kg body weight (bwt) respectively. Administration of CCL4 in untreated rats led to microcytic hypochromic anaemia, thrombocytopenia, increased erythrocyte fragility and stress induced leucocytosis accompanied with significant increase in neutrophils and decrease in lymphocyte counts. CCl4 also led to significant increase in serum transaminases (ALT and AST) and phosphatase (ALP) respectively compared with control animals. Also, CCL4 produced significant increase in serum blood urea nitrogen (BUN) and creatinine compared with normal rats. Pre-treatment with Cnidoscolus aconitifolius leaf extract brought about significant restoration of the haematological parameters to values that were comparable to those of the control with concomitant decrease in the activities of the marker of hepatic damage enzymes (ALT, AST and ALP), in a dose-dependent manner. Similarly, serum levels of blood urea nitrogen (BUN) and creatinine were also brought to near normal by the CA in a dose-dependent manner. From this study, we conclude that pre-exposure to Cnidoscolus aconitifolius leaf extract considerably reduced the effect of CCl4 on the blood parameters and ameliorated hepatic damage by the haloalkane. Keywords: Hepatotoxicity, Haemotoxicity, Carbon tetrachloride, Cnidoscolus aconitifolius, Rats.     

Erythrocyte membrane in protein-energy malnutrition: A23187-induced changes in osmotic fragility of human and rat erythrocytes

Erythrocytes from protein-energy malnourished children have been shown to have increased resistance to osmotic lysis (4). Osmotic fragility studies were carried out in protein-energy malnourished rats and A23187-induced changes in osmotic fragility were studied in rat and human erythrocytes. Rat erythrocytes were found to be much more sensitive to A23187 effect on osmotic fragility as compared to the human erythrocytes. Erythrocytes from protein-deficient rats but not from the energy-restricted rats showed increased resistance to osmotic lysis. A23187 (+Ca)-induced changes in osmotic fragility were not different between control and experimental erythrocytes, either for humans or rats. There was, however, a difference in the extent to which Na accumulation and K depletion occurred in erythrocytes from control and experimental animals after A23187 + Ca²⁺ treatment.     

A Mineral and Antioxidant-Rich Extract from the Red Marine Algae Alsidium corallinum Exhibits Cytoprotective Effects Against Potassium Bromate-Induced Erythrocyte Oxidative Damages in Mice

The present study was carried out to investigate potassium bromate toxicity in mice and the corrective effects of marine algae Alsidium corallinum. The red algae demonstrated its rich composition in phenols, triterpenes, flavonoids, alkaloids, tropolones, sodium, potassium, calcium, magnesium, iron, copper, and zinc. To confirm its antioxidant potential, an in vivo study was performed on adult mice. The animals were divided into four groups: group I were used as controls, group II received potassium bromate (0.5 g/L) via drinking water, group III received potassium bromate (0.5 g/L) by the same route as group II and 7 % of A. corallinum ethanolic extract via their diet, and group IV received only 7 % of algae. The potassium bromate-treated group showed a significant decrease in erythrocyte, platelet, hemoglobin, and hematocrit values and a significant increase in total white blood cells, compared to those of controls. While, superoxide dismutase, catalase, glutathione, and vitamin C values were decreased by potassium bromate treatment, lipid peroxidation (as malondialdehyde) and erythrocyte osmotic fragility values were increased. Interestingly, potassium bromate treatment showed significant genotoxic effects, as demonstrated by DNA degradation. These changes were confirmed by blood smears histopathological observations which were marked by a necrosis and a decrease of erythrocytes number. A. corallinum extract appeared to be effective against hematotoxic and genotoxic changes induced by potassium bromate, as evidenced by the improvement of the parameters cited above.     

Chemomodulatory action of Aloe vera on the profiles of enzymes associated with carcinogen metabolism and antioxidant status regulation in mice.

The effect of two doses (30 microl and 60 microl/day/mice daily for 14 days) of the fresh leaf pulp extract of Aloe vera was examined on carcinogen-metabolizing phase-I and phase-II enzymes, antioxidant enzymes, glutathione content, lactate dehydrogenase and lipid peroxidation in the liver of mice. The modulatory effect of the pulp extract was also examined on extrahepatic organs (lung, kidney and forestomach) for the activities of glutathione S-transferase, DT-diophorase, superoxide dismutase and catalase. The positive control mice were treated with butylated hydroxyanisole (BHA). Significant increases in the levels of acid soluble sulfhydryl (-SH) content, NADPH-cytochrome P450 reductase, NADH-cytochrome b5 reductase, glutathione S-transferase (GST), DT-diaphorase (DTD), superoxide dismutase (SOD), catalase, glutathione peroxidase (GPX) and glutathione reductase (GR) were observed in the liver. Aloe vera significantly reduced the levels of cytochrome P450 and cytochrome b5. Thus, Aloe vera is clearly an inducer of phase-II enzyme system. Treatment with both doses of Aloe caused a decrease in malondialdehyde (MDA) formation and the activity of lactate dehydrogenase in the liver, suggesting its role in protection against prooxidant-induced membrane and cellular damage. The microsomal and cytosolic protein was significantly enhanced by Aloe vera, indicating the possibility of its involvement in the induction of protein synthesis. BHA, an antioxidant compound, provided the authenticity of our assay protocol and response of animals against modulator. The pulp extract was effective in inducing GST, DTD, SOD and catalase as measured in extrahepatic organs. Thus, besides liver, other organs (lung, kidney and forestomach) were also influenced favorably by Aloe vera in order to detoxify reactive metabolites, including chemical carcinogens and drugs.     

库拉索芦荟幼苗对海水胁迫的响应

采用砂培试验,研究库拉索芦荟（Aloe vera）幼苗对海水胁迫的响应特征。结果表明：（1）30％海水处理20d,库拉索芦荟幼苗的干重与对照无显著差异,而30％海水处理库拉索芦荟的根干重明显高于10％海水及淡水处理;（2）海水胁迫下,库拉索芦荟幼苗中离子区域化明显：从地下部和地上部来看,Na^＋、Cl^＋明显在芦荟根部积累,海水比例越高,根部Na^＋、Cl^＋含量越大,而K^＋却相反;海水胁迫下芦荟地上部分功能叶片中Na^＋、Cl^＋含量最低,K^＋含量最高,而淡水处理从老叶到新叶,Na^＋、Cl^＋含量总是呈下降趋势,而K^＋正好相反;随海水胁迫在库拉索幼苗中Ca^2＋含量下降,而Mg^2＋含量七升;（3）随海水胁迫时间增加芦荟叶片质膜透性呈显著上升,MDA含量呈波动变化。     

Beneficial influence of dietary curcumin, capsaicin and garlic on erythrocyte integrity in high-fat fed rats

In rats rendered hyperlipidemic by maintaining them on a high-fat diet (30%) for 8 weeks, inclusion of spice principles [curcumin (0.2%) or capsaicin (0.015%)] or garlic (2.0%) in the diet produced significant hypotriglyceridemic effect. Plasma cholesterol remained unaffected in high-fat treatment. Hepatic triglyceride content was significantly higher in high-fat fed rats, and this increase was effectively countered by inclusion of the hypolipidemic spice agents -- curcumin, capsaicin or garlic in the diet. The lipid profile of erythrocyte membranes of hyperlipidemic rats was similar to basal controls. An examination of the osmotic fragility of erythrocytes in various groups indicated that the red blood cells of hyperlipidemic rats display a slight resistance to osmotic lysis. Inclusion of spice principles [curcumin (0.2%) or capsaicin (0.015%)] or garlic (2.0%) in the diet, which produced the hypotriglyceridemic effect, appeared to beneficially correct this altered osmotic fragility of erythrocytes. Activities of ouabain-sensitive Na(+),K(+)-ATPase as well as acetylcholinesterase of erythrocyte membranes in high-fat fed rats remained unaltered. Activity of Ca(2+),Mg(2+)-ATPase in erythrocyte membrane was significantly decreased in high-fat fed animals, whereas dietary spice principles and garlic countered this reduction in enzyme activity. In the absence of any change in the cholesterol/phospholipid molar ratio in the erythrocyte membrane, a decreased activity of membrane-bound Ca(2+),Mg(2+)-ATPase could have probably contributed to the accumulation of intracellular calcium leading to the diminished deformability of the erythrocytes in high-fat fed rats.     

Microturbidimetric determination of erythrocyte osmotic fragility in newborn,weanling and mature rats

A rapid, microturbidimetric method for recording red cell osmotic fragility using a Platelet Aggregometer is described. This method requires only 0.2 ml of whole blood and a fragility curve of 20 points can be determined in less than 1 hr. Measurement of the degree of hemolysis is based on the increasing transparency of the erythrocyte suspension when hemolysis takes place. Erythrocytes of immature animals are osmotically more resistant than those of adults and the change in osmotic resistance is not directly related to the percentage of reticulocytes.     

Lead effect on the oxidation resistance of erythrocyte membrane in rat triton-induced hyperlipidemia

The anemia observed in severe chronic lead poisoning is in part attributable to alterations in the erythrocyte physicochemical properties. Since they are partly related to the membrane lipid composition, the aim of the present study was to determine the effects of a triton-induced hyperlipidemia on the resistance to oxidation of erythrocyte membranes in lead-treated Wistar rats. Our results showed that triton administration to lead-treated rats induced an increase in erythrocyte choline phospholipid levels together with a significant decrease in the erythrocyte membrane lipid resistance to oxidation. These results led us to suggest that anemia in lead poisoning is linked to interactions between lead present in the membrane and plasma phospholipids. Their increase in rat hyperlipidemia induced by triton resulted in a decrease in the membrane resistance to oxidation and finally in an erythrocyte fragility leading to their destruction.     

Protective effect of glycine supplementation on the levels of lipid peroxidation and antioxidant enzymes in the erythrocyte of rats with alcohol-induced liver injury

We studied the effect of glycine supplementation on lipid peroxidation and antioxidants in the erythrocyte membrane, plasma and hepatocytes of rats with alcohol-induced hepatotoxicity. Administering ethanol (20%) for 60 days to male Wistar rats resulted in significantly elevated levels of erythrocyte membrane, plasma and hepatocyte thiobarbituric acid reactive substances (TBARS) as compared with those of the experimental control rats. Decreased activities of superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), glutathione peroxidase (GPx) and glutathione reductase (GR) were also observed on alcohol supplementation as compared with those of the experimental control rats. Glycine was administered at a dose of 0.6 g kg(-1) body weight to rats with alcohol-induced liver injury, which significantly decreased the levels of TBARS and significantly elevated the activities of SOD, CAT, GSH, GPx and GR in the erythrocyte membrane, plasma and hepatocytes as compared to that of untreated alcohol supplemented rats. Thus, our data indicate that supplementation with glycine offers protection against free radical-mediated oxidative stress in the erythrocyte membrane, plasma and hepatocytes of animals with alcohol-induced liver injury.     

Comparison of erythrocyte osmotic fragility among ectotherms and endotherms at three temperatures

1. Comparison of erythrocyte osmotic fragility (EOF) between various ectotherms and endotherms was investigated at 5, 25, and 38 degrees C. 2. We hypothesized that ectotherms might possess erythrocytes whose osmotic fragility would be less affected by temperature than those of endotherms. 3. Ectotherm erythrocytes were much more osmotically resistant than those of endotherms. 4. The EOF of ectotherms and endotherms showed similar responses to temperature. 5. It does not appear that the osmotic fragility of erythrocytes from ectotherms in this study are adapted to be less affected by temperature than those of endotherms. The highly osmotic resistant erythrocytes of ectotherms may alleviate the need for further adaptation for osmotic resistance.     

Comparative evaluation of aloe vera in the management of burn wounds in guinea pigs

An experimental study was designed using Hartley guinea pigs, who received full-thickness burns covering 3 percent of their body surface area by direct contact with a hot plate. A total of 40 animals were equally divided among four modalities of closed burn wound management as follows: group I: silver sulfadiazine (Silvadine); group II: aloe vera gel extract (Carrington Dermal Wound Gel); group III: salicylic acid cream (aspirin); and group IV: plain gauze occlusive dressing only. The dressings were changed daily, and the size and appearance of each burn wound were recorded until complete healing. On the sixth postburn day, quantitative burn wound cultures were made. The average time to complete healing in the control group was 50 days, and the only significant difference was found in the aloe vera-treated animals, which healed on an average of 30 days (p less than 0.02). Wound bacterial counts were effectively decreased by silver sulfadiazine (p = 0.015) and by aloe vera extract (p = 0.015). From our data it appears that aloe gel extracts permit a faster healing of burn wounds.