Low Density Lipoprotein Type Research Articles

Endogenous neuraminidase expression in atherosclerotic lesions of human aortic intima

Background and Aims: Desialylation is a certain type of low density lipoprotein (LDL) atherogenic modification; it may occur in arterial wall due to the action of endogenous neuraminidases (NEUs). This study was undertaken to test the above hypothesis.

The Description of Low Density Lipoprotein (LDL) Levels on Smoker and Non Smoker Adolescent in Buyan Hamlet, Pancasari Village, Sukasada District, Buleleng, Bali

Introduction: Low Density Lipoprotein (LDL) is a type of low-density lipoprotein and the most widely transported cholesterol in the body. Increased levels of LDL in the body can be affected by genetics, age, gender, obesity, physical activity, lifestyle, drug consumption and smoking. Substances in a cigarette can cause an increase of LDL levels. Increased of LDL cholesterol levels can cause Coronary Heart Disease (CHD). The purpose of this research is to know the description of Low Density Lipoprotein (LDL) levels on smoker and non-smoker adolescent in Buyan Hamlet, Pancasari Village, Sukasada District, Buleleng Bali. Method: The type of this research is descriptive. This research was conducted in April-May 2017, which used fasting blood samples of 42 respondents. Result: From the average result of LDL level in smoker adolescent that is 134,91 mg/dL higher than the average of LDL level in non-smoker adolescent that is 74,90 mg/dL. The result of LDL cholesterol levels was determined by 21 smoker adolescent respondents with the close to optimal category (100-129 mg/dL) as many as 9 people (42,8%), and 12 people (57,3%) with worry category (130-159 mg/dL). Whereas in 21 non-smoker adolescent respondents obtained result of LDL cholesterol level test with optimal category (<100 mg/dL) counted 18 people (87,71%) and 3 person (14,30%) with close to optimal category (100-129 mg/dL). Discussion: Based on the results of this research can be concluded that in smoker adolescent obtained LDL levels with close to optimal category and worrying whereas in non-smoker adolescents obtained LDL levels in the optimal category and close to optimal.

Targeting the Role of Lipoprotein (a) in Stroke

Stroke is the third leading cause of death in the United States, behind only heart disease and cancer, with over 140,000 associated deaths per year. Considerable research is ongoing to examine the role of modifiable risk factors which may cause or contribute to stroke. Although age and family history are generally considered to be the major risk factors, there are several modifiable and non-modifiable risk factors that are linked to the pathogenesis of a stroke. Lipoprotein (a), or Lp(a), is a type of low-density lipoprotein containing an integral apolipoprotein B100 (apoB100) component with an attached apolipoprotein A-1 (ApoA-1) isoform via a disulfide linkage. Lp(a) metabolism is of great interest as it sheds light on its role in pathogenesis of not only cardiovascular disorders but also stroke. Although Lp(a) has been identified as an "LDL-like particle", its metabolism differs from low density lipoprotein (LDL). Despite some ambiguity in the literature regarding the causative effect of Lp(a) on stroke, there are clear associations of high plasma Lp(a) concentration and risk of stroke. Furthermore, the small isoforms of ApoA-1-containing lipoproteins have been shown to increase atherogenicity in atherosclerotic patients. Currently, there is little research examining the importance of small molecule Lp(a) distribution and risk for stroke, both on a first-case and recurrent basis. Understanding the role of Lp (a) in stroke requires investigating its molecular mechanisms particularly the key microRNA (s) components that control its expression and function (s). Therefore, the main objective of this review is to discuss the broader link between Lp(a) and stroke and to identify opportunities for future investigation and potential research prospects on the role of Lp (a) in stroke.

Mua-3, a gene required for mechanical tissue integrity in Caenorhabditis elegans, encodes a novel transmembrane protein of epithelial attachment complexes.

Normal locomotion of the nematode Caenorhabditis elegans requires transmission of contractile force through a series of mechanical linkages from the myofibrillar lattice of the body wall muscles, across an intervening extracellular matrix and epithelium (the hypodermis) to the cuticle. Mutations in mua-3 cause a separation of the hypodermis from the cuticle, suggesting this gene is required for maintaining hypodermal–cuticle attachment as the animal grows in size postembryonically. mua-3 encodes a predicted 3,767 amino acid protein with a large extracellular domain, a single transmembrane helix, and a smaller cytoplasmic domain. The extracellular domain contains four distinct protein modules: 5 low density lipoprotein type A, 52 epidermal growth factor, 1 von Willebrand factor A, and 2 sea urchin-enterokinase-agrin modules. MUA-3 localizes to the hypodermal hemidesmosomes and to other sites of mechanically robust transepithelial attachments, including the rectum, vulva, mechanosensory neurons, and excretory duct/pore. In addition, it is shown that MUA-3 colocalizes with cytoplasmic intermediate filaments (IFs) at these sites. Thus, MUA-3 appears to be a protein that links the IF cytoskeleton of nematode epithelia to the cuticle at sites of mechanical stress.

Three types of low density lipoprotein receptor-deficient mutant have pleiotropic defects in the synthesis of N-linked, O-linked, and lipid-linked carbohydrate chains.

Biochemical, immunological, and genetic techniques were used to investigate the genetic defects in three types of low density lipoprotein (LDL) receptor-deficient hamster cells. The previously isolated ldlB, ldlC, and ldlD mutants all synthesized essentially normal amounts of a 125,000-D precursor form of the LDL receptor, but were unable to process this receptor to the mature form of 155,000 D. Instead, these mutants produced abnormally small, heterogeneous receptors that reached the cell surface but were rapidly degraded thereafter. The abnormal sizes of the LDL receptors in these cells were due to defective processing of the LDL receptor's N- and O-linked carbohydrate chains. Processing defects in these cells appeared to be general since the ldlB, ldlC, and ldlD mutants also showed defective glycosylation of a viral glycoprotein, alterations in glycolipid synthesis, and changes in resistance to several toxic lectins. Preliminary structural studies suggested that these cells had defects in multiple stages of the Golgi-associated processing reactions responsible for synthesis of glycolipids and in the N-linked and O-linked carbohydrate chains of glycoproteins. Comparisons between the ldl mutants and a large number of previously isolated CHO glycosylation defective mutants showed that the genetic defects in ldlB, ldlC, and ldlD cells were unique and that only very specific types of carbohydrate alteration could dramatically affect LDL receptor function.