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Biomedical subjects

G H Cocolas

Publications and source records attributed to G H Cocolas.

At least 19 recordsLinked to original sources
PubMed1985

Hypolipidemic activity of 6-amino-2-mercapto-5-methyl-pyrimidine-4-carboxylic acid and related derivatives in rodents.

6-Amino-2-mercapto-5-methylpyrimidine-4-carboxylic acid proved to be a potent hypolipidemic agent in rodents at the low dose of 20 mg/kg/d. The agent effectively reduced the liver enzyme activities required for the synthesis of triglycerides and cholesterol. Lower lipid levels in tissue were observed in mice but not in rats. Preliminary studies indicate that the agent accelerated the excretion of cholesterol and its metabolites from the body. The agents lowered the low-density lipoprotein (LDL) cholesterol content and raised the high-density lipoprotein (HDL) cholesterol content. These changes in lipoprotein cholesterol content suggest that the agent may be helpful in protecting against coronary disease. The agent is more effective than the commercially available agent, i.e., clofibrate at 150 mg/kg/d.

Animals↗
PubMed1985

Comparison of the hypolipidemic activity of cyclic vs. acyclic imides.

Two series of nitrogen-substituted cyclic and acyclic imides were examined for hypolipidemic activity in mice after dosing for 16 days at a dose of 20 mg/kg per day. The hypolipidemic activity of the unsubstituted, N-butyl, N-3-oxobutyl, and N-2-carboxyethyl derivatives of diacetimide and succinimide were compared as well as the unsubstituted and N-substituted dibenzimide and diphenimide. It was shown that an imide functionality incorporated into a ring was not necessary for hypocholesterolemic activity. Good hypocholesterolemic activity was observed in both series of acyclic and cyclic imides. However, a cyclic imido structure was a necessary requirement for good hypotriglyceridemic activity. A decrease in hypotriglyceridemic activity was noted when comparing the cyclic imides to their respective acyclic congeners.

Animals↗
PubMed1984

Hypolipidemic activity of 4-phenyl-5,5-dicarbethoxy-2-pyrrolidinone in rodents.

A series of pyrrolidinones have been reported to possess hypolipidemic activity in mice. The most active agent, 4-phenyl-5-5-dicarbethoxy-2-pyrrolidinone, effectively lowered both serum cholesterol and triglyceride levels at 20-30 mg/kg/d. The agent suppressed liver mitochondrial citrate exchange, phosphatidate phosphohydrolase, and sn-glycerol-3-phosphate acyl transferase activities. Lipid content of the liver, small intestine, and serum lipoprotein fractions was reduced by drug treatment, but lipid levels increased in the bile and fecal samples, suggesting the drug accelerated lipid excretion. The mode of action of the pyrrolidinone appears similar to that of the cyclic imides.

Animals↗
PubMed1984

Hypolipidemic activity of 3-N-(1',8'-Naphthalimido)propionic acid in rodents.

3-N-(1',8'-Naphthalimido)propionic acid was synthesized and shown to effectively lower both serum cholesterol and triglyceride levels in rats and mice. In hyperlipidemic mice, serum lipid levels were lowered significantly, approaching normal levels of cholesterol and below normal levels of triglyceride. The serum lipid levels were reduced due to accelerated clearance of cholesterol via the biliary route as well as a lowering of available acetyl CoA in the cytoplasm for liver de novo cholesterol and triglyceride syntheses. The liver regulatory enzyme of fatty acid and triglyceride syntheses were depressed by drug treatment. Significant reduction of liver lipids as well as the lipid content of the lipoprotein fractions were observed. The agent possessed a safe therapeutic index when used as a hypolipidemic agent.

Animals↗
PubMed1984

Hypolipidemic activity of phthalimide derivatives V: Reduced and hydrolytic products of simple cyclic imides.

A series of cyclic imides and related compounds have previously been shown to possess hypolipidemic activity at the low dose level of 20 mg/kg/d. Hydrolytic and reduced products of the cyclic imides were synthesized and examined to discern if possible metabolic products were the active chemical species of these hypolipidemic agents. Phthalimide proved to be the most active cyclic imide tested. Unfortunately, the new products did not, in general, improve hypolipidemic activity in rodents. The exceptions were piperidine which demonstrated improved hypotriglyceridemic activity, and 3,4,5,6-dibenzohomopiperidin-2-one, which demonstrated improved hypocholesterolemic activity compared to phthalimide.

Animals↗
PubMed1984

Hypolipidemic activity of 4-pyrimidinecarboxylic acids in CF1 mice.

A series of 4-pyrimidinecarboxylic acids were evaluated for hypolipidemic activity in mice at 20-30 mg/kg/d ip. A number of these derivatives were observed to be active at this dose. Substitution of the hydroxyl group in position 2 and 6 of the 4-pyrimidinecarboxylic acid with a sulfhydryl and an amino group, respectively, led to a compound which produced a greater than 40% reduction of serum cholesterol and triglyceride levels in mice. Similarly, a compound which was substituted with an amino group in position 2 and an isobutyl group in position 5 led to equally potent activity as a hypolipidemic agent.

Animals↗
PubMed1983

Hypolipidemic activity of substituted 2-pyrrolidinones in rodents.

A series of substituted 2-pyrrolidinones was evaluated for hypolipidemic activity at 20 and 30 mg/kg/day in CF1 male mice. 4-Phenyl-5,5-dicarbethoxy-2-pyrrolidinone was the most potent compound at 30 mg/kg/day, reducing serum triglyceride levels 52% after 14 days of dosing and serum cholesterol levels 48% after 16 days of dosing. 4-Phenyl-5-carbethoxy-2-pyrrolidinone and 4-phenyl-3,5,5-tricarbethoxy-2-pyrrolidinone also demonstrated significant activity. Those compounds which contained a phenyl substituent were more potent than either the unsubstituted, the alkyl, or the dicarbethoxy 2-pyrrolidinone analogues.

Animals↗
PubMed1983

Antihyperlipidemic activity of phthalimide analogues in rodents.

Phthalimide analogues have been shown to effectively lower serum cholesterol and triglyceride levels in rats and mice. The mode of action of these agents was not to suppress the appetite of animals, but rather to reduce the activities of key enzymes in the early synthesis of liver cholesterol and fatty acids in the triglyceride pathway. Phthalimide analogues were effective in accelerating biliary excretion of cholesterol and blocking its absorption from the gut. After 16 days dosing, it was evident that higher levels of lipids were being excreted than in control mice. The major serum lipoprotein fractions were reduced in cholesterol, triglyceride, and neutral lipid content, but not phospholipid content in rats after 14 days of administration.

Animals↗
PubMed1983

Antihyperlipidemic activity of saccharin analogues in rodents.

Saccharin analogues were observed to be potent antihyperlipidemic agents at 20 mg/kg/day in rodents, significantly reducing both serum cholesterol and triglyceride levels in both normal and atherogenic mice. The saccharin analogues suppressed in vitro and in vivo liver enzymatic activity of acetyl-CoA synthetase, citrate lyase, and mitochondrial citrate exchange leading to a reduction of available cytoplasmic acetyl-CoA, which is required for the synthesis of cholesterol and fatty acids. Liver acetyl-CoA carboxylase, phosphatidate phosphohydralase, and glycerol-3-phosphate acyl transferase activities were markedly reduced by the saccharin analogues. Suppression of these enzymes would lead to a reduction of triglyceride synthesis. The saccharin analogues accelerated bile excretion of cholesterol metabolites and increased the fecal excretion of the cholesterol, triglycerides, neutral lipids, and phospholipids. The liver and plasma lipoprotein lipid content (including cholesterol, triglycerides, and neutral lipids) was markedly reduced by the saccharin analogues, whereas phospholipid content was elevated. The reduction of lipid content of serum chylomicron, very low-density, low-density, and high-density lipoprotein fractions by the saccharin analogues indicates that these agents may be useful in controlling hyperlipidemic diseases where specific lipoprotein fractions are elevated.

Animals↗
PubMed1983

Hypolipidemic activity of phthalimide derivatives IV: Further chemical modification and investigation of the hypolipidemic activity of N-substituted imides.

A further investigation of N-substituted derivatives of phthalimide for hypolipidemic activity has revealed that the chain length, as well as the type of substitution on the N-alkyl chain of phthalimide is critical for biological activity. In these studies the hypolipidemic activity was not improved by extending the chain length beyond five carbon atoms in the alkyl and alkanoic acid series. Imido nitrogen substituents, other than alkanoic acids, methyl ketones, and alkyl groups, caused a reduction in hypolipidemic activity, e.g., hydroxy, amino, hydroxymethyl, or carbethoxy. Reduction of the keto group in the side chain to an alcohol, as well as forming derivatives of the keto group, did not improve the hypolipidemic activity with the exception of 1-N-phthalimidobutan-3-one semicarbazone. This compound demonstrated improved hypocholesterolemic activity over phthalimide and 1-N-phthalimidobutan-3-one. Substitution of the 3-position of the aromatic moiety of phthalimide with an amino or nitro group, as well as substituting a pyridine or cyclohexyl ring for the phenyl ring, led to the loss of hypolipidemic activity.

Animals↗
PubMed1983

Hypolipidemic activity of phthalimide derivatives. 2. N-phenylphthalimide and derivatives.

A series of substituted N-phenylphthalimide derivatives was synthesized and examined for their ability to lower serum cholesterol and triglyceride levels in mice at 20 (mg/kg)/day, ip. Of the newly synthesized compounds, the most potent compound, o-(N-phthalimido)acetophenone, lowered serum cholesterol 57% after 16 days and lowered serum triglyceride levels 44% after 14 days. o-(N-Phthalimido)acetophenone was observed to be active in both normogenic (normal blood lipids levels) and hyperlipidemic mice and normogenic rats. In the latter, the reduction of serum lipids was reversible. The mode of this compound appeared to be multiple, including blockage of the de novo synthesis of lipids and acceleration of the excretion of lipids. The lipoprotein fractions of rat blood were reduced significantly in cholesterol, triglyceride, and neutral lipid content after 14 days treatment with o-(N-phthalimido)acetophenone.

Acetate-CoA Ligase↗
PubMed1983

Hypolipidemic activity of phthalimide derivatives. 3. A comparison of phthalimide and 1,2-benzisothiazolin-3-one 1,1-dioxide derivatives to phthalimidine and 1,2-benzisothiazoline 1,1-dioxide congeners.

Previously it has been observed that N-substituted phthalimide derivatives with chain lengths of four carbon or oxygen atoms showed potent hypolipidemic activity in rodents at 20 (mg/kg)/day ip. The 1,2-benzisothiazolin-3-one 1,1-dioxide (saccharin) nucleus, itself, had also been observed to be active at the same dose. An investigation was undertaken to examine a series of 1,2-benzisothiazolin-3-one 1,1-dioxide analogues for their hypolipidemic activity in mice and to compare them to their respective phthalimide congeners. In addition, a series of 1,2-benzisothiazoline 1,1-dioxide and phthalimidine analogues was prepared, and their hypolipidemic activity was compared to the phthalimide analogues. These studies show that the respective congeners of 1,2-benzisothiazolin-3-one 1,1-dioxide compared favorably to phthalimide congeners in reducing serum triglyceride and cholesterol levels in male CF1 mice at 20 (mg/kg)/day ip. Of the saccharin derivatives, 3-oxo-1,2-benzisothiazoline-2-propionic acid 1,1-dioxide was the most effective in lowering serum cholesterol levels by 53% after 16 days dosing and 3-oxo-1,2-benzisothiazoline-2-valeric acid 1,1-dioxide lowered serum triglycerides 56% after 14 days dosing. The 1,2-benzisothiazoline 1,1-dioxide and phthalimidine compounds were less active as hypolipidemic agents than their 1,2-benzisothiazolin-3-one 1,1-dioxide and phthalimide analogues, respectively.

Animals↗
PubMed1981

Effects of imide analogs on enzymes required for cholesterol and fatty acid synthesis.

Twelve imide analogs were examined for their ability to lower serum cholesterol and triglyceride levels in mice. Potent activity was observed for compounds containing a phthalimide or saccharin ring structure. The ability to lower serum cholesterol appears to be related to the ability to suppress acetyl-CoA synthetase activity. The availability of acetyl-CoA in the cytoplasm is a key regulatory component for cholesterol and fatty acid synthesis. The capacity to reduce serum triglycerides was related directly to the ability of the compound to inhibit acetyl-CoA carboxylase activity, the regulatory enzyme of fatty acid synthesis.

Acetate-CoA Ligase↗
PubMed1979

Binding of mono- and bis-N-substituted benzoquinolinium halides to butyrylcholinesterase: fluorescence measurements.

The dissociation constants (Kdiss) of mono-and bis-N-substituted benzoquinolinium salts from butyrylcholinesterase were determined by the disappearance of the fluorescence of the free ligand. The Kdiss value determined by this method agreed closely with the dissociation constants (KI,s) of the free enzyme obtained by steady-state kinetic studies. The results indicate that the N-substituted benzoquinolinium salts with a strong binding ability to butyrylcholinesterase also are potent inhibitors of the esterolytic properties of the enzyme. Enzyme binding is favored by the coplanar structure and does not require a high concentration of charge on the onium function. The shape of the hydrophobic structures markedly influences binding.

Animals↗
PubMed1979

Hypolipidemic activity of phthalimide derivatives. 1. N-Substituted phthalimide derivatives.

The general lipid-lowering action of the N-substituted phthalimide derivatives reported herein, as well as the activity of potassium phthalimide, implicates the phthalimide moiety as possessing hypolipidemic activity in rodents. Compounds containing substituents with chain lengths of four carbon or oxygen atoms showed the best hypolipidemic activity in the series tested. Tests involving 1-N-phthalimidobutan-3-one demonstrated a dose-dependent hypolipidemic action free of estrogenic side effects, with no apparent deposition of cholesterol in body organs, and with a high therapeutic index. Further work on the hypolipidemic activity of phthalimido, as well as other imido compounds, is underway.

Animals↗
PubMed1977

Potent reversible anticholinesterase agents. Bis- and mono-N-substituted benzoquinolinium halides.

A number of bis- and mono-N-substituted benzoquinolinium salts and their analogues were prepared and evaluated as inhibitors of acetylcholinesterase (AcChE) and butyrylcholinesterase (BuChE). These compounds were also used to help identify some of the morphologic characteristics of the surface at or near the active sites of the cholinesterases. The shape, size, configuration, and conformation of the onium moieties of the quaternary ammonium compounds were found to be the important factors in their anticholinesterase activity. A high concentration of the positive charge of the quaternary ammonium compound is not a critical factor for the cholinesterase inhibitory activity. The order of decreasing potency of cholinesterase inhibition of the benzoquinolinium compounds was found to be acridinium greater than phenanthridinium greater than 5,6-benzoquinolinium greater than 7,8-benzoquinolinium. The inhibitory activity of the monobenzoquinolinium halides against cholinesterases is influenced by the N-substituent. A bis-quaternary ammonium compound with a flexible bridge that links the two nitrogen atoms was found to be more potent in inhibiting AcChE and less potent in inhibiting BuChE than a bis-quaternary ammonium compound with a rigid bridge. The acridinium and phenanthridinium derivatives of the benzoquinolinium compounds are very potent reversible inhibitors against both AcChE and BuChE.

Cholinesterase Inhibitors↗