Detection, evaluation, and treatment of high blood cholesterol in adults (Adult Treatment Panel III)

In 1901 a physician, Archibald Garrod, observed a patient with black urine. He used this simple observation to demonstrate that a single mutant gene can produce a discrete block in a biochemical pathway, which he called an “inborn error of metabolism”. Garrod’s brilliant insight anticipated by 40 years the one gene-one enzyme concept of Beadle and Tatum. In similar fashion the chemist Linus Pauling and the biochemist Vernon Ingram, through study of patients with sickle cell anemia, showed that mutant genes alter the amino acid sequences of proteins. Clearly, many fundamental advances in biology were spawned by perceptive studies of human genetic diseases (1). We began our work in 1972 in an attempt to understand a human genetic disease, familial hypercholesterolemia or FH. In these patients the concentration of cholesterol in blood is elevated many fold above normal and heart attacks occur early in life. We postulated that this dominantly inherited disease results from a failure of end-product repression of cholesterol synthesis. The possibility fascinated us because genetic defects in feedback regulation had not been observed previously in humans or animals, and we hoped that study of this disease might throw light on fundamental regulatory mechanisms. Our approach was to apply the techniques of cell culture to unravel the postulated regulatory defect in FH. These studies led to the discovery of a cell surface receptor for a plasma cholesterol transport protein called low density lipoprotein (LDL) and to the elucidation of the mechanism by which this receptor mediates feedback control of cholesterol synthesis (2,3). FH was shown to be caused by inherited defects in the gene encoding the LDL receptor, which disrupt the normal control of cholesterol metabolism. Study of the LDL receptor in turn led to the understanding of receptor-mediated endocytosis, a genera! process by which cells communicate with each other through internalization of regulatory and nutritional molecules (4). Receptor-mediated endocytosis differs from previously described biochemical pathways because it depends upon the continuous and highly controlled movement of membraneembedded proteins from one cell organelle to another in a process termed

https://science.sciencemag.org/content/sci/232/4746/34.full.pdf

A receptor-mediated pathway for cholesterol homeostasis.

Flavonoids are nearly ubiquitous in plants and are recognized as the pigments responsible for the colors of leaves, especially in autumn. They are rich in seeds, citrus fruits, olive oil, tea, and red wine. They are low molecular weight compounds composed of a three-ring structure with various substitutions. This basic structure is shared by tocopherols (vitamin E). Flavonoids can be subdivided according to the presence of an oxy group at position 4, a double bond between carbon atoms 2 and 3, or a hydroxyl group in position 3 of the C (middle) ring. These characteristics appear to also be required for best activity, especially antioxidant and antiproliferative, in the systems studied. The particular hydroxylation pattern of the B ring of the flavonoles increases their activities, especially in inhibition of mast cell secretion. Certain plants and spices containing flavonoids have been used for thousands of years in traditional Eastern medicine. In spite of the voluminous literature available, however, Western medicine has not yet used flavonoids therapeutically, even though their safety record is exceptional. Suggestions are made where such possibilities may be worth pursuing.

The Effects of Plant Flavonoids on Mammalian Cells:Implications for Inflammation, Heart Disease, and Cancer

A B S T R AC T BACKGROUND The order and magnitude of pathologic processes in Alzheimer’s disease are not well understood, partly because the disease develops over many years. Autosomal dominant Alzheimer’s disease has a predictable age at onset and provides an opportunity to determine the sequence and magnitude of pathologic changes that culminate in symptomatic disease. METHODS In this prospective, longitudinal study, we analyzed data from 128 participants who underwent baseline clinical and cognitive assessments, brain imaging, and cerebrospinal fluid (CSF) and blood tests. We used the participant’s age at baseline assessment and the parent’s age at the onset of symptoms of Alzheimer’s disease to calculate the estimated years from expected symptom onset (age of the participant minus parent’s age at symptom onset). We conducted cross-sectional analyses of baseline data in relation to estimated years from expected symptom onset in order to determine the relative order and magnitude of pathophysiological changes. RESULTS Concentrations of amyloid-beta (Aβ)42 in the CSF appeared to decline 25 years before expected symptom onset. Aβ deposition, as measured by positron-emission tomography with the use of Pittsburgh compound B, was detected 15 years before expected symptom onset. Increased concentrations of tau protein in the CSF and an increase in brain atrophy were detected 15 years before expected symptom onset. Cerebral hypometabolism and impaired episodic memory were observed 10 years before expected symptom onset. Global cognitive impairment, as measured by the Mini–Mental State Examination and the Clinical Dementia Rating scale, was detected 5 years before expected symptom onset, and patients met diagnostic criteria for dementia at an average of 3 years after expected symptom onset. CONCLUSIONS We found that autosomal dominant Alzheimer’s disease was associated with a series of pathophysiological changes over decades in CSF biochemical markers of Alzheimer’s disease, brain amyloid deposition, and brain metabolism as well as progressive cognitive impairment. Our results require confirmation with the use of longitudinal data and may not apply to patients with sporadic Alzheimer’s disease. (Funded by the National Institute on Aging and others; DIAN ClinicalTrials.gov number, NCT00869817.)

/pdf/clinical-and-biomarker-changes-in-dominantly-inherited-66jpsco78g.pdf

Clinical and Biomarker Changes in Dominantly Inherited Alzheimer’s Disease

Natural killer T (NKT) lymphocytes express an invariant T cell antigen receptor (TCR) encoded by the Valpha14 and Jalpha281 gene segments. A glycosylceramide-containing alpha-anomeric sugar with a longer fatty acyl chain (C26) and sphingosine base (C18) was identified as a ligand for this TCR. Glycosylceramide-mediated proliferative responses of Valpha14 NKT cells were abrogated by treatment with chloroquine-concanamycin A or by monoclonal antibodies against CD1d/Vbeta8, CD40/CD40L, or B7/CTLA-4/CD28, but not by interference with the function of a transporter-associated protein. Thus, this lymphocyte shares distinct recognition systems with either T or NK cells.

http://science.sciencemag.org/content/sci/278/5343/1626.full.pdf

CD1d-restricted and TCR-mediated activation of valpha14 NKT cells by glycosylceramides.

Oxidative stress or signaling is widely implicated in apoptosis, ischemia and mitogenesis Previously, our group reported that the hydrogen peroxide (H2O2)-dependent activation of phospholipase D2 (PLD2) in PC12 cells is involved in anti-apoptotic effect However, the precise mechanism of PLD2 activation by H2O2 was not revealed To find H2O2-dependent PLD2-regulating proteins, we immunoprecipitated PLD2 from PC12 cells and found that glyceraldehyde 3-phosphate dehydrogenase (GAPDH) coimmunoprecipitated with PLD2 upon H2O2 treatment This interaction was found to be direct by in vitro reconstitution of purified GAPDH and PLD2 In vitro studies also indicated that PLD2-associated GAPDH was modified on its reactive cysteine residues Koningic acid, an alkylator of GAPDH on catalytic cysteine residue, also increased interaction between the two proteins in vitro and enhanced PLD2 activity in PC12 cells Blocking H2O2-dependent modification of GAPDH with 3-aminobenzamide resulted in the inhibition of the GAPDH/PLD2 interaction and attenuated H2O2-induced PLD2 activation in PC12 cells From the results, we suggest that H2O2 modifies GAPDH on its catalytic cysteine residue not only to inactivate the dehydrogenase activity of GAPDH but also to endow GAPDH with the ability to bind PLD2 and the resulting association is involved in the regulation of PLD2 activity by H2O2

https://onlinelibrary.wiley.com/doi/pdf/10.1046/j.1471-4159.2003.01755.x

Hydrogen peroxide induces association between glyceraldehyde 3-phosphate dehydrogenase and phospholipase D2 to facilitate phospholipase D2 activation in PC12 cells

tiydroxylation of monacolin L to monacolin J by M. ruberlt8). The present communication deals with the transformation of monacolin J to monacolin K by a cell-free extract of M. ruber and by living cells of Paecilomyces viridis. The latter fungus is known to produce compactin (ML-236B) analogs, another family of HMG-CoAreductase inhibitors6). M. ruber M4681 was grown aerobically in a medium containing glycerol 7%, glucose 3%, meat extract 3%, peptone 0.8%, NaNO3 0.2% and MgSO4à\"7H2O0.1% at 25°C for 2 days. The culture broth (100ml) was filtered and the mycelia were washed with 50 him potassium phosphate buffer, pH 8.3, containing 2mMEDTA.The washed mycelia (1.5g) were ground at 0°C for 5 minutes with 3 g of alumina and 0.8 ml of 50 mMpotassium phosphate buffer, pH 8.3, containing 2mM EDTA, imM

https://www.jstage.jst.go.jp/article/antibiotics1968/43/12/43_12_1621/_pdf

Biosynthesis of monacolins: conversion of monacolin J to monacolin K (mevinolin).

Pannorin, a naphthopyrone that inhibits 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis, was isolated from a culture broth of Chrysosporium pannorum M10539 by solvent extraction, Bio-Gel P-6 column chromatography and reverse phase HPLC (Silica ODS). Spectroscopic analyses of the compound yielded 4,8,10-trihydroxy-5-methyl-2H-naphtho[1,2-b]pyran-2-one as the proposed structure. Pannorin inhibited HMG-CoA reductase and in vitro sterol synthesis 50% at a concentration of 160 microM.

Akira Endo

Papers

Hydrogen peroxide induces association between glyceraldehyde 3-phosphate dehydrogenase and phospholipase D2 to facilitate phospholipase D2 activation in PC12 cells

Biosynthesis of monacolins: conversion of monacolin J to monacolin K (mevinolin).

Pannorin, a new 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor produced by Chrysosporium pannorum.

Inhibition of the accumulation of lipid droplets in macrophage J774 by bafilomycin B1 and destruxin E.

Biochemical aspect of HMG CoA reductase inhibitors.