Glutathione peroxidase (GPx) is the general name of an enzyme family with peroxidase activity whose main biological role is to protect the organism from oxidative damage. The biochemical function of glutathione peroxidase is to reduce lipid hydroperoxides to their corresponding alcohols and to reduce free hydrogen peroxide to water.
The connecting peptide, or C-peptide, is a short 31-amino-acid polypeptide that connects insulin's A-chain to its B-chain in the proinsulin molecule. In the context of diabetes or hypoglycemia, a measurement of C-peptide blood serum levels can be used to distinguish between different conditions with similar clinical features.
Diabetic neuropathy is various types of nerve damage associated with diabetes mellitus. Symptoms depend on the site of nerve damage and can include motor changes such as weakness; sensory symptoms such as numbness, tingling, or pain; or autonomic changes such as urinary symptoms. These changes are thought to result from a microvascular injury involving small blood vessels that supply nerves. Relatively common conditions which may be associated with diabetic neuropathy include distal symmetric polyneuropathy; third, fourth, or sixth cranial nerve palsy; mononeuropathy; mononeuropathy multiplex; diabetic amyotrophy; and autonomic neuropathy.
Pyridoxamine is one form of vitamin B6. Chemically it is based on a pyridine ring structure, with hydroxyl, methyl, aminomethyl, and hydroxymethyl substituents. It differs from pyridoxine by the substituent at the 4-position. The hydroxyl at position 3 and aminomethyl group at position 4 of its ring endow pyridoxamine with a variety of chemical properties, including the scavenging of free radical species and carbonyl species formed in sugar and lipid degradation and chelation of metal ions that catalyze Amadori reactions.
Advanced glycation end products (AGEs) are proteins or lipids that become glycated as a result of exposure to sugars. They are a bio-marker implicated in aging and the development, or worsening, of many degenerative diseases, such as diabetes, atherosclerosis, chronic kidney disease, and Alzheimer's disease.
A complication in medicine, or medical complication, is an unfavorable result of a disease, health condition, or treatment. Complications may adversely affect the prognosis, or outcome, of a disease. Complications generally involve a worsening in the severity of the disease or the development of new signs, symptoms, or pathological changes that may become widespread throughout the body and affect other organ systems. Thus, complications may lead to the development of new diseases resulting from previously existing diseases. Complications may also arise as a result of various treatments.
Diabetic nephropathy, also known as diabetic kidney disease, is the chronic loss of kidney function occurring in those with diabetes mellitus. Diabetic nephropathy is the leading causes of chronic kidney disease (CKD) and end-stage renal disease (ESRD) globally. The triad of protein leaking into the urine, rising blood pressure with hypertension and then falling renal function is common to many forms of CKD. Protein loss in the urine due to damage of the glomeruli may become massive, and cause a low serum albumin with resulting generalized body swelling (edema) so called nephrotic syndrome. Likewise, the estimated glomerular filtration rate (eGFR) may progressively fall from a normal of over 90 ml/min/1.73m2 to less than 15, at which point the patient is said to have end-stage renal disease. It usually is slowly progressive over years.
Chemical antagonists impede the normal function of a system. They function to invert the effects of other molecules. The effects of antagonists can be seen after they have encountered an agonist, and as a result, the effects of the agonist is neutralized. Antagonists such as dopamine antagonist slow down movement in lab rats. Although they hinder the joining of enzymes to substrates, Antagonists can be beneficial. For example, not only do angiotensin receptor blockers, and angiotensin-converting enzyme (ACE) inhibitors work to lower blood pressure, but they also counter the effects of renal disease in diabetic and non-diabetic patients. Chelating agents, such as calcium di sodium defeated, fall into the category of antagonists and operate to minimize the lethal effects of heavy metals such as mercury or lead.
Epalrestat is a carboxylic acid derivative and a noncompetitive and reversible aldose reductase inhibitor used for the treatment of diabetic neuropathy, which is one of the most common long-term complications in patients with diabetes mellitus. It reduces the accumulation of intracellular sorbitol which is believed to be the cause of diabetic neuropathy, retinopathy and nephropathy It is well tolerated, with the most commonly reported adverse effects being gastrointestinal issues such as nausea and vomiting, as well as increases in certain liver enzymes. Chemically, epalrestat is unusual in that it is a drug that contains a rhodanine group. Aldose reductase is the key enzyme in the polyol pathway whose enhanced activity is the basis of diabetic neuropathy. Aldose reductase inhibitors (ARI) target this enzyme. Out of the many ARIs developed, ranirestat and fidarestat are in the trial stage. Others have been discarded due to unacceptable adverse effects or weak efficacy. Epalrestat is the only ARI commercially available. It is easily absorbed into the neural tissue and inhibits the enzyme with minimum side effects.
Endothelial NOS (eNOS), also known as nitric oxide synthase 3 (NOS3) or constitutive NOS (cNOS), is an enzyme that in humans is encoded by the NOS3 gene located in the 7q35-7q36 region of chromosome 7. This enzyme is one of three isoforms that synthesize nitric oxide (NO), a small gaseous and lipophilic molecule that participates in several biological processes. The other isoforms include neuronal nitric oxide synthase (nNOS), which is constitutively expressed in specific neurons of the brain and inducible nitric oxide synthase (iNOS), whose expression is typically induced in inflammatory diseases. eNOS is primarily responsible for the generation of NO in the vascular endothelium, a monolayer of flat cells lining the interior surface of blood vessels, at the interface between circulating blood in the lumen and the remainder of the vessel wall. NO produced by eNOS in the vascular endothelium plays crucial roles in regulating vascular tone, cellular proliferation, leukocyte adhesion, and platelet aggregation. Therefore, a functional eNOS is essential for a healthy cardiovascular system.
NAD(P)H dehydrogenase [quinone] 1 is an enzyme that in humans is encoded by the NQO1 gene. This protein-coding gene is a member of the NAD(P)H dehydrogenase (quinone) family and encodes a 2-electron reductase (enzyme). This FAD-binding protein forms homodimers and performs two-electron reduction of quinones to hydroquinones and of other redox dyes. It has a preference for short-chain acceptor quinones, such as ubiquinone, benzoquinone, juglone and duroquinone. This gene has an important paralog NQO2. This protein is located in the cytosol.
Ectonucleotide pyrophosphatase/phosphodiesterase family member 1 is an enzyme that in humans is encoded by the ENPP1 gene.
MAPK/MAK/MRK overlapping kinase is an enzyme that in humans is encoded by the RAGE gene.
Complications of diabetes are secondary diseases that are a result of elevated blood glucose levels that occur in diabetic patients. These complications can be divided into two types: acute and chronic. Acute complications are complications that develop rapidly and can be exemplified as diabetic ketoacidosis (DKA), hyperglycemic hyperosmolar state (HHS), lactic acidosis (LA), and hypoglycemia. Chronic complications develop over time and are generally classified in two categories: microvascular and macrovascular. Microvascular complications include neuropathy, nephropathy, and retinopathy; while cardiovascular disease, stroke, and peripheral vascular disease are included in the macrovascular complications.
3-Deoxyglucosone (3DG) is a sugar that is notable because it is a marker for diabetes. 3DG reacts with protein to form advanced glycation end-products (AGEs), which contribute to diseases such as the vascular complications of diabetes, atherosclerosis, hypertension, Alzheimer's disease, inflammation, and aging.
Saroglitazar is a drug for the treatment of type 2 diabetes mellitus and dyslipidemia. It is approved for use in India by the Drug Controller General of India. Saroglitazar is indicated for the treatment of diabetic dyslipidemia and hypertriglyceridemia with type 2 diabetes mellitus not controlled by statin therapy. In clinical studies, saroglitazar has demonstrated reduction of triglycerides (TG), LDL cholesterol, VLDL cholesterol, non-HDL cholesterol and an increase in HDL cholesterol a characteristic hallmark of atherogenic diabetic dyslipidemia (ADD). It has also shown anti-diabetic medication properties by reducing the fasting plasma glucose and HBA1c in diabetes patients.
Type 3c diabetes is diabetes that comes secondary to pancreatic diseases, involving the exocrine and digestive functions of the pancreas. It also occurs following surgical removal of the pancreas.
Gosogliptin is a drug for the treatment of type II diabetes. It is in the class of dipeptidyl peptidase-4 (DPP-4) inhibitors. It was discovered and developed through Phase 1 and Phase 2 by Pfizer. The crystal structure of DPP-4 in complex with gosogliptin is available. Its metabolism, excretion and pharmacokinetics in rat, dog and human have been described. A cost efficient route has been published. Other studies including Phase 3 studies were conducted in Russia. It is approved for use in Russia.
Diabetic embryopathy refers to congenital maldevelopments that are linked to maternal diabetes. Prenatal exposure to hyperglycemia can result in spontaneous abortions, perinatal mortality, and malformations. Type 1 and Type 2 diabetic pregnancies both increase the risk of diabetes induced teratogenicity. The rate of congenital malformations is similar in Type 1 and 2 mothers because of increased adiposity and the age of women with type 2 diabetes. Genetic predisposition and different environmental factors both play a significant role in the development of diabetic embryopathy. Metabolic dysfunction in pregnant mothers also increases the risk of fetal malformations.
Sanjay Kalra is an Indian endocrinologist working at Bharti Hospital, Karnal, Haryana. Kalra is the Immediate Past President of Endocrine Society of India and Vice President of South Asian Federation of Endocrine Societies. He also serves on the executive council of the Research Society for Study of Diabetes in India. He has over 1000 PubMed indexed articles to his name, and has fostered bilateral and multilateral links between various Afro Asian countries in the field of endocrinology. He has developed the terms Glucocrinology and Lipocrinology. and the Gluco Coper tool to assess coping mechanisms. Winner of the DAWN Award (2009). He has also published the concepts of diabetes fatigue syndrome, euthymia in diabetes, quaternary prevention in endocrinology, and quinary prevention.
