Antidyslipidemic and antioxidant activity of the constituents isolated from the leaves of Calophyllum inophyllum.

In continuation of our drug discovery program on Indian medicinal plants, we isolated bioactive compounds (1-5) from the leaves of Calophyllum inophyllum and evaluated their antidyslipidemic activity in triton induced hyperlipidemia model. The calophyllic acid (1A) and isocalophyllic acid (1B) mixture, canophyllic acid (4) and amentoflavone (5) showed dose dependent lipid lowering activity in in vivo experiments. The compounds 1A+1B mixture and 3 also showed good in vitro antioxidant activity.

Indole-based fibrates as potential hypolipidemic and antiobesity agents.

Hypolipidemic and antiobesity effects of the newly synthesized indole-based fibrates were evaluated in Triton WR-1339 and high fat diet (HFD)-induced hyperlipidemic rats. Preliminary screening of all the synthesized compounds was done by using an acute model (Triton model), in which compounds 3f and 3l showed significant antidyslipidemic activity. Furthermore, these compounds 3f and 3l were found to induce significant weight loss in the visceral fat mass of HFD-fed hyperlipidemic rats without affecting the normal feeding behavior. Histological examination of the liver of rats supplemented with 3f and 3l revealed a significant decrease in steatosis when compared to the effect of the standard drug fenofibrate. Additional effects such as an increase in lecithin cholesterol acyl-transferase (LCAT) enzyme level and increased receptor mediated catabolism of I(131)-low density lipoproteins (LDL) confirm and reinforce the efficacy of both of these compounds as a new class of dual-acting hypolipidemic and antiobesity agents.

Syntheses and evaluation of glucosyl aryl thiosemicarbazide and glucosyl thiosemicarbazone derivatives as antioxidant and anti-dyslipidemic agents.

A series of N-per-O-acetyl-glucosyl arylthiosemicarbazide and thiosemicarbazone derivatives have been synthesized and evaluated for their in vivo anti-dyslipidemic and in vitro antioxidant activities. Among 16 compounds tested, 3 compounds showed potent anti-dyslipidemic activity and 6 compounds showed potent antioxidant and scavenger of oxygen free radicals activity.

Lipid peroxidation and antioxidant enzyme status in oral carcinoma patients.

OBJECTIVE: To measure the lipid peroxidation and endogenous antioxidant enzyme status in oral carcinoma and the protective role of exogenous antioxidants. MATERIAL AND METHODS: 20 new cases of histologically proven oral squamous cell carcinoma, 20 of leukoplakia and 20 age and sex matched healthy conrols were included. Intra oral pH of patients and controlled were measured by quantitative litmus paper test and serum was analysed for malonialdehyde (MDA), super oxide bismutase (SOD), catalase and glutathione peroxidase (GP). Patients with leukoplakia were treated with exogenous antioxidants for 3 months and the same were reassessed. RESULTS: Oral pH of oral cancer patients was neutral (PH-7) but that of leukoplakia and controls were mildly acidic (6.64 and 6.58 respectively). Serum malonialdehyde levels were highest in oral cancer group. With antioxidant enzymes super oxide bismutase, catalase and glutathione peroxidase different pattern was noticed. Antioxidant enzymes remained almost the same (P > 0.005 each) in patients with leukoplakia after 3 months of vitamin A,C and E. but there was marginal increase in catalase level (P<0.05). CONCLUSION: This study shows the positive benefit of vitamin (A,C,E) and nutrition supplementation on the antioxidant enzyme defense system hence prevention of oral carcinogenesis in patients with leukoplakia.

Lipid lowering activity of Phyllanthus niruri in hyperlipemic rats.

The lipid lowering activity (LLA) of Phyllanthus niruri has been studied in triton and cholesterol fed hyperlipemic rats. Serum lipids were lowered by P. niruri extract orally fed (250 mg/kg b.w.) to the triton WR-1339 induced hyperlipemic rats. Chronic feeding of this drugs (100 mg/kg b.w.) in animals simultaneously fed with cholesterol (25 mg/kg b.w.) for 30 days caused lowering in the lipids and apoprotein levels of VLDL and LDL in experimental animals. The LLA of this drug is mediated through inhibition of hepatic cholesterol biosynthesis, increased faecal bile acids excretion and enhanced plasma lecithin: cholesterol acyltransferase activity.

Syntheses and biological evaluation of alkanediamines as antioxidant and hypolipidemic agents.

A new series of compounds belonging to N,N'- [bis (1-aryl-6-hydroxy-hex-2-ene-1-one-3-yl)-1,n-alkanediamines (2-5a-f) have been synthesized and evaluated for antioxidant and hypolipidemic activities. Amongst all the synthesized compounds, seven compounds namely 2c, 2e, 4c, 5b, 5c, 5e and 5f exhibit potent antioxidant activity. These compounds have also been evaluated for hypolipidemic activity.

Syntheses and biological evaluation of 3-substituted amino-1-aryl-6-hydroxy-hex-2-ene-1-ones as antioxidant and hypolipidemic agents.

A new series of compounds belonging to 3-substituted amino-1-aryl-6-hydroxy-hex-2-ene-1-ones (4-12a-e) have been synthesized and evaluated for antioxidant and hypolipidemic activities. Amongst all the synthesized compounds, seven compounds, namely 5b, 5d, 6e, 8a, 8b, 10b and 11a, exhibit better antioxidant activity than probucol. Two compounds, 5d and 10b, have been evaluated in detail for antioxidant and hypolipidemic activities and show comparable activity profile to that of probucol and guggulipid. From the present study it may be postulated that the mechanism of action of these compounds could be through activation of lecithin cholesterol acyltransferase (LCAT), liver lipolytic activity, increased faecal bile acid secretion and inhibition of hepatic cholesterol biosynthesis.

Hypolipidemic activity of Achyranthus aspera Linn in normal and triton induced hyperlipemic rats.

The alcoholic extract of A. aspera, at 100 mg/kg dose lowered serum cholesterol (TC), phospholipid (PL). triglyceride (TG) and total lipids (TL) levels by 60, 51, 33 and 53% respectively in triton induced hyperlipidemic rats. The chronic administration of this drug at the same doses to normal rats for 30 days, lowered serum TC, PL, TG and TL by 56, 62, 68 and 67% respectively followed by significant reduction in the levels of hepatic lipids. The faecal excretion of cholic acid and deoxycholic acid increased by 24 and 40% respectively under the action of this drug. The possible mechanism of action of cholesterol lowering activity of A. aspera may be due to rapid excretion of bile acids causing low absorption of cholesterol.

Alterations in in vitro functional activities of alveolar macrophages exposed in vivo to mineral dusts.

To determine whether macrophages exposed to mineral dusts are altered, rats were exposed intratracheally to one of several mineral dusts, held 8 days, their lungs washed and the cellular composition of the fluid characterized morphologically and functionally. The number of cells recovered from lung washings of exposed rats increased 2 to 5 times relative to control rats; however, the percentage of such cells that were macrophages, or were capable of phagocytosis, adherence to glass or metabolism of carbohydrates via the hexose monophosphate shunt as indicated by reduction of nitroblue tetrazolium, were reduced. Silica dust produced the greatest effect, corresponding qualitatively to earlier in vivo studies.