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Excess adiposity is the most important risk in the development of type 2 diabetes mellitus (T2DM). Adipose tissue produces several proteins (adipocytokines) such as leptin, adiponectin, resistin, tumor necrosis factor-a, and IL-6, that modulate sensitivity and appear to play an important role in the pathogenesis, diabetes, dyslipidemia, inflammation, and atherosclerosis. Visfatin, also known as pre-B cell colony-enhancing factor (PBEF), is a cytokine that is highly expressed in visceral fat and was originally isolated as a secreted factor that synergizes with IL-7 and stem cell factors to promote the growth of B cell precursors. Visfatin homologs have been identified in carp, invertebrate mollusks, and bacteria, as well as in vertebrates, including humans and the mouse. It has been postulated to play a role in innate immunity.
Visfatin exerts mimetic effects that are dose-dependent and quantitatively similar to stimulating muscle and adipocyte glucose transport, and in inhibiting hepatocyte glucose production. Intravenous injection of recombinant visfatin in mice decreased plasma glucose in a dose-dependent fashion. In keeping with its mimetic effects, visfatin was as effective in reducing hyperglycemia in deficient diabetic mice. Visfatin was also found to be bound to and activate receptor, causing receptor phosphorylation and the activation of downstream signaling molecules. However, visfatin did not compete for binding to the receptor, indicating that the two proteins were recognized by different regions of the receptor. Thus, visfatin might play a role in glucose homeostasis and dysregulation in biosynthesis or signal transduction, and might contribute to the pathogenesis of diabetes.

Magnesium-dependent phosphatase 1 (MDP1) is a memeber of the HAD-like hydrolase superfamily. MDP1 is a magnesium-dependent phosphatase which may act as a tyrosine phosphatase. MDP1 is inhibited by vanadate and zinc, and slightly by calcium.

Methionine aminopeptidase 1 (METAP1) is a member of the peptidase M24A family. METAP1 removes the amino-terminal methionine from nascent proteins. METAP1 releases N-terminal amino acids, preferentially methionine, from peptides and arylamides. METAP1 is essential for normal progression through the cell cycle. The active site of METAP1 contains 2 adjacent divalent metal ions linked by a water molecule or hydroxide ion.

ADP-ribosylarginine hydrolase (ADPRH) is a member of the ADP-ribosylglycohydrolase family. ADPRH catalyzes the removal of mono-ADP-ribose from arginine residues of proteins in the ADP-ribosylation cycle. The human ADPRH enzyme is DTT-independent as opposed to the rat and mouse enzymes, which require DTT for maximal activity.

DCXR catalyzes the NADPH-dependent reduction of numerous pentoses, tetroses, trioses, alpha-dicarbonyl molecules and L-xylulose. DCXR takes part in the uronate cycle of glucose metabolism. DCXR participates in the water absorption and cellular osmoregulation in the proximal renal tubules by producing xylitol, an osmolyte, thus preventing osmolytic stress from occurring in the renal tubules.

Aldolase C Fructose-Bisphosphate (ALDOC) belongs to the class I fructose-bisphosphate aldolase family. ALDOC is a glycolytic enzyme which catalyzes the reversible aldol cleavage of fructose-1,6-biphosphate and fructose 1-phosphate to dihydroxyacetone phosphate and either glyceraldehyde-3-phosphate or glyceraldehydes respectively. ALDOC is expressed exclusively in the hippocampus and Purkinje cells of the brain.

Syntaxin-binding protein 6 (STXBP6) binds components of the SNARE complex and takes part in regulating SNARE complex configuration. STXBP6 forms non-fusogenic complexes with SNAP25 and STX1A and modulates the formation of SNARE complexes and exocytosis.

SULT1E1 catalyzes the sulfate conjugation of many hormones, neurotransmitters, drugs, and xenobiotic compounds. These cytosolic enzymes are different in their tissue distributions and substrate specificities. Decreased SULT1E1 expression is linked with estrogen-dependent endometrial carcinomas. Altered cellular proliferation was detected in cells stably expressing SULT1E1.

Phosphatidylinositol transfer protein beta isoform (PITPNB) is found in the cytoplasm, where it catalyzes the transfer of phosphatidylinositol (PI) and phosphatidylcholine (PC) between membranes. PITPNB mobilizes PI from the endoplasmic reticulum and regulates its release from stored vesicles in the Golgi network. PITPNB is extensively expressed in various tissues.

Glutathione S-transferase mu 5 (GSTM5) belongs to the glutathione s-transferase (GST) family of proteins. There are 8 families of GST proteins, specifically alpha, kappa, mu, omega, pi, sigma, theta and zeta, each of which is comprised of proteins which have various functions throughout the cell. GSTM5 belongs to the mu class of enzymes which function in the detoxification of electrophilic compounds, including carcinogens, therapeutic drugs, environmental toxins and products of oxidative stress, by conjugation with glutathione. GSTM5 has an imperative role in detoxification. GSTM5 conjugates reduced glutathione to a large number of exogenous and endogenous hydrophobic electrophiles.

SNF8 belongs to the SNF8 family of vacuolar sorting proteins and is restricts to both the nucleus and the cytoplasm. SNF8 is a subunit of the endosomal sorting complex essential for transport II (ESCRT-II), which is necessary for multivesicular body (MVB) formation and sorting of endosomal cargo proteins into MVBs. The MVB pathway facilitates transfer of transmembrane proteins into the lumen of the lysosome for degradation. Additionally, the ESCRT-II complex takes part in transcription regulation by contributing to derepression of transcription by RNA polymerase II, probably by its interface with ELL.

Obg-like ATPase 1 (OLA1) acts as a negative regulator of the cellular antioxidant response independent of transcriptional processes. OLA1 curbs the antioxidant response via nontranscriptional mechanisms. OLA1 hydrolyzes ATP, and can also hydrolyze GTP with lower efficiency. OLA1 is clearly down-regulated by DNA damage-inducing agents. OLA1 is expressed in all tissues; however it is more abundant in the testis, liver, lung, and brain. OLA1 is overexpressed in a number of malignancies, including cancers of the colon, rectum, ovary, lung, stomach, and uterus.

Non-Metastatic Cells 4 or NME4, is a nucleoside diphosphate kinase located in the mitochondria, and is part of the NDK family of proteins. NME4 ais a very common enzyme that enhances transfer of gamma-phosphates, through a phosphohistidine as a intermediate, between dioxynucleoside tri- and diphosphates. NME4 is originated from the nm23 gene. NME4 has a crucial part in the creation of nucleoside triphosphates that are not ATP.

Protein Phosphatase 2C alpha is a member of the PP2C family of Ser/Thr protein phosphatases. PP2C family members are known to be negative regulators of cell stress response pathways. This phosphatase dephosphorylates, and negatively regulates the activities of, MAP kinases and MAP kinase kinases. It has been shown to inhibit the activation of p38 and JNK kinase cascades induced by environmental stresses. This phosphatase can also dephosphorylate cyclin-dependent kinases, and thus may be involved in cell cycle control. Overexpression of this phosphatase is reported to activate the expression of the tumor suppressor gene TP53/p53, which leads to G2/M cell cycle arrest and apoptosis. Three alternatively spliced transcript variants encoding two distinct isoforms have been described.
Protein phosphatase 2C(PP2C?) is a Mn2+- or Mg2+-dependent protein serine/threonine phosphatase that is essential for regulating cellular stress response in eukaryotes.

BPGM is found at high concentrations in red blood cells where it binds to and decreases the oxygen affinity of hemoglobin. PGM deficiency increases the oxygen affinity of cells. BPGM is a multifunctional enzyme that catalyzes 2,3-DPG synthesis through its synthetase activity, and 2,3-DPG degradation using its phosphatase activity. BPGM has phosphoglycerate phosphomutase activity. Mutations in BPGM cause hemolytic anemia. BPGM catalyzes the reaction of EC 5.4.2.1 (mutase) and EC 3.1.3.13 (phosphatase), but with a reduced activity.

Syntaxin is membrane integrated Q-SNARE protein participating in exocytosis. Syntaxin is composed of an N-terminal regulatory domain (Habc), a SNARE domain (known as H3), and a single C-terminal transmembrane domain. The SNARE (H3) domain binds to both synaptobrevin and SNAP-25 forming the core SNARE complex. Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localization of both synaptic vesicles and calcium channels to the presynaptic active zone. Syntaxins function in this vesicle fusion process. Syntaxins also serve as a substrate for botulinum neurotoxin type C, a metalloprotease that blocks exocytosis and has high affinity for a molecular complex that includes the alpha-latrotoxin receptor which produces exocytosis.

GOT2 is a pyridoxal phosphate-dependent enzyme which is found in cytoplasmic and inner-membrane mitochondrial forms, GOT1 and GOT2. GOT2 takes part in amino acid metabolism and the urea and tricarboxylic acid cycles. Both enzymes are homodimeric and demonstrate close homology.

AKR1B1 is part of the aldo/keto reductase superfamily, which consists of more than 40 known enzymes and proteins. AKR1B1 catalyzes the reduction several aldehydes, including the aldehyde form of glucose, and thus involved in the development of diabetic complications by catalyzing the reduction of glucose to sorbitol. AKR1B1 catalyzes the NADPH-dependent reduction of a wide variety of carbonyl-containing compounds to their corresponding alcohols. Transgenic mice over expressing human aldose reductase show that AKR1B1 is a key player in ischemic injury and impairment of functional and metabolic recovery after ischemia. Aldose Reductase is an obligatory mediator of TNF-alpha signaling leading to an increase in the expression of adhesion molecules and increased binding of monocytes to the endothelium. AKR1B1 is a critical regulator of TNF-alpha-induced apoptotic signaling in endothelial cells.

Fatty Acid Amide Hydrolase 2 (FAAH2) shares a conserved protein motif with the amidase signature family of enzymes. FAAH2 catalyzes the hydrolysis of a broad range of bioactive lipids, including those from the 3 main classes of fatty acid amides; N-acylethanolamines, fatty acid primary amides and N-acyl amino acids. FAAH2 is also degrades bioactive fatty acid amides to their corresponding acids, thus helping to end the signaling functions of these molecules. FAAH2 prefers monounsaturated acyl chains as a substrate.

Neuron-specificenolase also caled NSE is a glycolytic isoenzyme which is situated in central and peripheral neurons and neuroendocrine cells. Enolase-2 is released into the CSF when neural tissue is injured. Neoplasms derived from neural or neuroendocrine tissue release Enolase-2 into the blood. Enolase-2 is a useful substance that has been detected in patients with certain tumors, such as neuroblastoma, small cell lung cancer, medullary thyroid cancer, carcinoid tumors, pancreatic endocrine tumors, and melanoma. ENO2 is 1 of the 3 enolase isoenzymes found in mammals. ENO2 isoenzyme, is found in mature neurons and cells of neuronal origin. An exchange from alpha enolase to gamma enolase occurs in neural tissue during development in rats and primates.

Glutathione S-transferase, also known as GST, is an antioxidant enzyme. It is the primary defense mechanism from reactive oxygen in the cell. The enzyme GST reduces hydroperoxides of lipids via a Se-independent glutathione peroxidase actions. GST detoxifies peroxidation of lipids bi-products, for example 4-hydroxynonenal.

NAP1L1 is a member of the nucleosome assembly protein (NAP) family. NAP1L1 protein plays a part in DNA replication, modulating chromatin formation and regulation of cell proliferation.

CBR1 is one of numerous monomeric, NADPH-dependent oxidoreductases having ubiquistly specificity for carbonyl compounds. CBR1 is broadly distributed in human tissues. CBR1 metabolizes toxic environmental quinones and pharmacological relevant substrates. CBR1 converts prostaglandin E2 to prostaglandin F2-alpha.

Thiamin pyrophosphokinase 1 (TPK1) is a homodimer which catalyzes the phosphorylation of thiamine to thiamine pyrophosphate. TPK1 is found in the heart, kidney, testis, small intestine and peripheral blood leukocytes, and at very low levels in a variety of tissues. TPK1 gene defects cause the thiamine metabolism dysfunction syndrome type 5, episodic encephalopathy type (THMD5), which is an autosomal recessive metabolic disorder due to an inborn error of thiamine metabolism.