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Hyocholic Acid
Hyocholic acid or 3α,6α,7α-trihydroxy-5β-cholan-24-oic acid is a bile acid found as one of the main forms in pig, and at low concentrations in other species including humans. Hyocholic acid differs from the primary bile acids found in humans by having a third hydroxyl group in the α-conformation at the 6-position, unlike cholic acid, which has a 12-hydroxyl, and chenodeoxycholic acid which has neither a 6- or 12-hydroxyl. It also differs from the muricholic acids found in rodents, as they are 6β-hydroxylated, and can have the 7-hydroxyl in either the α- or β- positions, forming α- or β-muricholic acids. Hyocholic acid is conjugated in the liver before secretion with taurine or with glycine to give taurohyocholate or glycohyocholates. Bacterial 7α-dehydroxylation in the colon produces the secondary bile acid, hyodeoxycholic acid. Epimerization of the 7-hydroxyl to the β-position is found in ω-muricholic acid (also known as β-hyocholic acid). The enzyme responsib ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bile Acid
Bile acids are steroid acids found predominantly in the bile of mammals and other vertebrates. Diverse bile acids are synthesized in the liver. Bile acids are conjugated with taurine or glycine residues to give anions called bile salts. Primary bile acids are those synthesized by the liver. Secondary bile acids result from bacterial actions in the colon (anatomy), colon. In humans, taurocholic acid and glycocholic acid (derivatives of cholic acid) and taurochenodeoxycholic acid and glycochenodeoxycholic acid (derivatives of chenodeoxycholic acid) are the major bile salts. They are roughly equal in concentration. The salts of their 7-alpha-dehydroxylated derivatives, deoxycholic acid and lithocholic acid, are also found, with derivatives of cholic, chenodeoxycholic and deoxycholic acids accounting for over 90% of human biliary bile acids. Bile acids comprise about 80% of the organic compounds in bile (others are phospholipids and cholesterol). An increased secretion of bile acids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxyl Group
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy groups. Both the negatively charged anion , called hydroxide, and the neutral radical , known as the hydroxyl radical, consist of an unbonded hydroxy group. According to IUPAC definitions, the term ''hydroxyl'' refers to the hydroxyl radical () only, while the functional group is called a ''hydroxy group''. Properties Water, alcohols, carboxylic acids, and many other hydroxy-containing compounds can be readily deprotonated due to a large difference between the electronegativity of oxygen (3.5) and that of hydrogen (2.1). Hydroxy-containing compounds engage in intermolecular hydrogen bonding increasing the electrostatic attraction between molecules and thus to higher boiling and melting points than found for compounds that lack this func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholic Acid
Cholic acid, also known as 3α,7α,12α-trihydroxy-5β-cholan-24-oic acid is a primary bile acid that is insoluble in water (soluble in alcohol and acetic acid), it is a white crystalline substance. Salts of cholic acid are called cholates. Cholic acid, along with chenodeoxycholic acid, is one of the two major bile acids produced by the liver, where it is synthesized from cholesterol. These two major bile acids are roughly equal in concentration in humans. Derivatives are made from cholyl-CoA, which exchanges its CoA with either glycine, or taurine, yielding glycocholic and taurocholic acid, respectively. Cholic acid downregulates cholesterol-7-α-hydroxylase (rate-limiting step in bile acid synthesis), and cholesterol does the opposite. This is why chenodeoxycholic acid, and not cholic acid, can be used to treat gallstones (because decreasing bile acid synthesis would supersaturate the stones even more). Cholic acid and chenodeoxycholic acid are the most important human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chenodeoxycholic Acid
Chenodeoxycholic acid (CDCA; also known as chenodesoxycholic acid, chenocholic acid and 3α,7α-dihydroxy-5β-cholan-24-oic acid) is a bile acid. Salts of this carboxylic acid are called chenodeoxycholates. Chenodeoxycholic acid is one of the main bile acids. It was first isolated from the bile of the domestic goose, which gives it the "cheno" portion of its name (Greek: χήν = goose). Structure Chenodeoxycholic acid and cholic acid are the two primary bile acids in humans. Chenodeoxycholic acid has two hydroxyl groups and is modified with the addition of another hydroxyl group to produce cholic acid. Some other mammals have muricholic acid or deoxycholic acid rather than chenodeoxycholic acid. It occurs as a white crystalline substance insoluble in water but soluble in alcohol and acetic acid, with melting point at 165–167 °C. Biosynthesis and function Chenodeoxycholic acid is synthesized in the liver from cholesterol via several enzymatic steps. Like other bile a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muricholic Acids
Muricholic acids are a group of bile acids found as one of the main forms in mice, which gives them their name, and at low concentrations in other species. Muricholic acids differ from the primary bile acids found in humans, cholic acid and chenodeoxycholic acid, by having a hydroxyl group in the β- configuration at the 6-position. The orientation of the hydroxyl group at the 7 position defines α- or β-muricholic acid. Muricholic acids are detectable at low concentrations in human urine. The three major bile acids in germ-free mice are cholic acid, α-muricholic, and β-muricholic acids. In conventional mice with a normal microbiome, ω-muricholic acid, and various sulfated forms are also found. Conjugation with taurine (to give tauromuricholic acids which are the main forms), or with glycine (to give glycomuricholic acids) takes place in the liver before secretion. The enzyme responsible for the 6-hydroxylation reactions forming muricholates in rodents is the cytochrome P450 '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyodeoxycholic Acid
Hyodeoxycholic acid, also known as 3α,6α-Dihydroxy-5β-cholan-24-oic acid or HDCA, is a secondary bile acid, one of the metabolic byproducts of intestinal bacteria. It differs from deoxycholic acid in that the 6α-hydroxyl is in the 12 position in the former. The 6α-hydroxyl group makes HDCA a hydrophilic acid, a property it shares with hyocholic acid. HDCA is present in mammalian species in different proportions. It is the main acid constituent of hog bile, and for this reason it was used industrially as precursor for steroid synthesis before total synthesis became practical. Metabolism In rat intestinal microflora hyodeoxycholic acid is produced by a Gram-positive rod—termed HDCA-1—from several isomers of hyocholic acid and muricholic acid. In pigs with a normal gastrointestinal flora the majority of hyodeoxycholic acid found in bile is of secondary nature, but a small amount was also found in germ free pigs, which supports the hypothesis that HDCA may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytochrome P450
Cytochromes P450 (CYPs) are a Protein superfamily, superfamily of enzymes containing heme as a cofactor (biochemistry), cofactor that functions as monooxygenases. In mammals, these proteins oxidize steroids, fatty acids, and xenobiotics, and are important for the clearance (pharmacology), clearance of various compounds, as well as for hormone synthesis and breakdown. In 1963, Ronald W. Estabrook, Estabrook, David Y. Cooper, Cooper, and Otto Rosenthal, Rosenthal described the role of CYP as a catalyst in steroid hormone synthesis and drug metabolism. In plants, these proteins are important for the biosynthesis of secondary metabolite, defensive compounds, fatty acids, and hormones. CYP enzymes have been identified in all kingdom (biology), kingdoms of life: animals, plants, fungus, fungi, protists, bacteria, and archaea, as well as in viruses. However, they are not omnipresent; for example, they have not been found in ''Escherichia coli''. , more than 300,000 distinct CYP proteins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholestasis
Cholestasis is a condition where bile cannot flow from the liver to the duodenum. The two basic distinctions are an obstructive type of cholestasis where there is a mechanical blockage in the duct system that can occur from a gallstone or malignancy, and metabolic types of cholestasis which are disturbances in bile formation that can occur because of genetic defects or acquired as a side effect of many medications. Classification is further divided into acute or chronic and extrahepatic or intrahepatic. Signs and symptoms The signs and symptoms of cholestasis vary according to the cause. In case of sudden onset, the disease is likely to be acute, while the gradual appearance of symptoms suggests chronic pathology. In many cases, patients may experience pain in the abdominal area. Localization of pain to the upper right quadrant can be indicative of cholecystitis or choledocholithiasis, which can progress to cholestasis. Pruritus or itching is often present in many patients with c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sleeve Gastrectomy
Sleeve gastrectomy is a surgical weight-loss procedure in which the stomach is reduced to about 15% of its original size, by surgical removal of a large portion of the stomach along the greater curvature. The result is a sleeve or tube like structure. The procedure permanently reduces the size of the stomach, although there could be some dilation of the stomach later on in life. The procedure is generally performed laparoscopically and is irreversible. A meta-analysis of 174,772 participants published in The Lancet in 2021 found that bariatric surgery was associated with 59% and 30% reduction in all-cause mortality among obese adults with or without type 2 diabetes respectively. This meta-analysis also found that median life-expectancy was 9.3 years longer for obese adults with diabetes who received bariatric surgery as compared to routine (non-surgical) care, whereas the life expectancy gain was 5.1 years longer for obese adults without diabetes. Procedure Sleeve gastrectomy w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Obesity
Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it may negatively affect health. People are classified as obese when their body mass index (BMI)—a person's weight divided by the square of the person's height—is over ; the range is defined as overweight. Some East Asian countries use lower values to calculate obesity. Obesity is a major cause of disability and is correlated with various diseases and conditions, particularly cardiovascular diseases, type 2 diabetes, obstructive sleep apnea, certain types of cancer, and osteoarthritis. Obesity has individual, socioeconomic, and environmental causes. Some known causes are diet, physical activity, automation, urbanization, genetic susceptibility, medications, mental disorders, economic policies, endocrine disorders, and exposure to endocrine-disrupting chemicals. While a majority of obese individuals at any given time are attempting to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
