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Cystatins are a superfamily of cysteine proteinase inhibitors found in both plants and animals. They comprise a group of proteinase inhibitors, widely distributed in tissues and body fluids, and form tight complexes with cysteine proteases such as cathepsin B, H, L and S. Cystatin C, a secreted molecule of this family, is of interest from biochemical, medicine and evolutionary points of view. Cystatin C is increased in patients with malignant diseases, and is related to the insufficiency of renal function and appears to be a better marker than creatinine. On the other hand, low levels of cystatin C involve cause the breakdown of the elastic laminae and subsequently, the atherosclerosis and abdominal aortic aneurysm.

L-Selectin belongs to a family of divalent cation-dependent carbohydrate-binding glycoproteins or adhesion molecules. The L-Selectin molecule is composed of various domains: one homologous to lectins, one to epidermal growth factor, and two to the consensus repeat units found in C3/C4 binding proteins.
L-selectin is expressed constitutively on lymphocytes, monocytes and granulocytes and interacts specifically with carbohydrate groups on activated endothelial cells. L-Selectin may be shed by proteolytic cleavage and circulating levels in biological fluids may be used as an indicator of various pathological conditions. L-Selectin is cleaved by ADAM17.
L-selectin works as a "homing receptor" for leukocytes to enter secondary lymphoid tissues via the high endothelial venules. Ligands present on endothelial cells will attach to leukocytes expressing L-selectin, which causes the leukocytes to become localized at that juncture. The receptor is also located on the cell surfaces of "naive" T cells, which have not yet encountered their particular antigen. This surface expression is lost following the cells activation.

XCL1 is a small cytokine belonging to the XC chemokine family that is also known as lymphotactin. It is located in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to another chemokine called XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

C-type lectin domain family 7 member A 1 or CLEC7A is a protein, that in the innate immune system, acts against fungal pathogens. CLEC7A can be found in the immune system response cells such as monocytes, macrophages & neutrophils, or in dendritic and T cells. The protein is enhanced by macrophages by using GM-CSF, IL-4, or IL-13, or diminishes by dexamethasone, IL-10 and LPS.

Secernin 1 (SCRN1) which is a member of the peptidase C69 family, regulates exocytosis in mast cells. SCRN1 increases both the level of secretion and the sensitivity of mast cells to stimulation with calcium.

Chromosome 19 Open Reading Frame 80 (C19ORF80) is a significant new regulator of lipid metabolism which regulates serum triglyceride levels, possibly by promoting ANGPTL3 cleavage. C19ORF80 belongs to the ANGPTL protein family. C19ORF80 is a hormone which specifically promotes pancreatic beta cell proliferation and beta cell mass expansion, thus improving glucose tolerance. C19ORF80 is mainly expressed in the liver; it is also expressed in adipose tissues. C19ORF80 is expressed in response to food intake and stimulated by insulin.

Chromgranin-A is part of the neuroendocrine secretory protein family. CHGA is located in secretory vesicles of neurons and endocrine cells. Chromgranin-A is a precursor to three biologically active peptides; vasostatin, pancreastatin, and parastatin. These peptides act as autocrine or paracrine negative modulators of the neuroendocrine system. Other peptides, including chromostatin, beta-granin, WE-14 and GE-25, are also derived from the full-length protein. Chromgranin-A has numerous biological activities on some tissues and organs and exerts a large spectrum of homeostatic actions, including antifungal and antimicrobial effect, modulation of cell adhesion, and inhibition of parathyroid hormone secretion.

VAMP8 also called endobrevin, is the main component of a SNARE complex involved in the docking and fusion of synaptic vesicles with the presynaptic membrane. VAMP8 protein is involved in the regulatation of enzyme secretion in pancreatic acinar cells and plays a part in the abscission of the midbody during cell division, which leads to completely separate daughter cells. VAMP8 is essential for dense-granule secretion in platelets. VAMP8 is related with the perinuclear vesicular structures of the early endocytic compartment. VAMP8 interacts particularly with the soluble NSF-attachment protein (alpha-SNAP), through an VAMP8-containing SNARE complex.

RELM-gamma is a novel member of the resistin-like molecule/found in inflammatory zone (RELM/FIZZ) family in mice and rats. Microarray and real-time RT-PCR experiments revealed a repression of RELMgamma mRNA in nasal respiratory epithelium of cigarette smoke-exposed versus untreated rats. The analysis of the physiological tissue-specific expression revealed highest expression in hematopoietic tissues, suggesting a cytokine-like role for RELM-gamma. RELM-gamma-mRNA is detectable in bone marrow, spleen, and lung as well as in peripheral blood granulocytes. Promyelocytic HL60 cells transfected with a RELM-gamma expression plasmid have an increased proliferation rate compared to mock-transfected cells and display an altered response to retinoic acid-induced granulocytic differentiation. Taken together, these data provide the first experimental evidence that RELM-gamma is a secreted molecule with a restricted expression pattern that may play a role in promyelocytic differentiation.

EPO a is a member of the EPO/TPO family and encodes a secreted, glycosylated cytokine composed of four alpha helical bundles. EPO a is found in the plasma and regulates red cell production by promoting erythroid differentiation and initiating hemoglobin synthesis. EPO a also has neuroprotective activity against a variety of potential brain injuries and antiapoptotic functions in several tissue types.

GH-releasing peptides (GHRPs) are synthetic peptides that like GHRH act directly on pituitary somatotrophs to stimulate GH release. Growth hormone (GH) release is stimulated by a variety of synthetic secretagogues, of which growth hormone-releasing hexapeptide (GHRP-6) has been most thoroughly studied; it is thought to have actions at both pituitary and hypothalamic site.

SEPT5 is a member of the septin gene family of nucleotide binding proteins which were initially defined in yeast as cell division cycle regulatory proteins. Septins are extremely conserved in yeast, Drosophila, and mouse and seem to regulate cytoskeletal organization. Interference of septin function disrupts cytokinesis and results in high multinucleate or polyploid cells.

Thymalfasin is a synthetic analogue of thymosin-alpha-1, a 28-amino acid protein derived from the precursor protein prothymosin-alpha. Exhibiting a variety of immunoregulating properties, thymosin-alpha-1 induces differentiation of murine T-cell precursors and human thymocytes and the terminal differentiation of functionally immature cord blood lymphocytes and induces production of IL-2, high affinity IL-2 receptors, and B-cell growth factors by peripheral blood mononuclear cells. T-helper and cytotoxic/suppressor T-cell populations are targets of thymosin activity. Thymosin-alpha-1 has been shown to increase the efficiency of antigen presentation by macrophages and to be an endogenous modulator of alpha-thrombin activity.

TRIM21 is a member of the tripartite motif (TRIM) family. The TRIM motif includes three zinc-binding domains, a RING, a B-box type 1 and a B-box type 2, and a coiled-coil region. The 52 kDa Ro protein is part of the RoSSA ribonucleoprotein, which includes a single polypeptide and one of four small RNA molecules. The RoSSA particle localizes to both the cytoplasm and the nucleus. Ro/SSA interacts with autoantigens in patients with Sjogren syndrome and systemic lupus erythematosus. Ribonucleoprotein particle is composed of a single polypeptide and one of four small RNA molecules. The RoSSA is present in all mammalian cells studied but has no known function. At least 2 isoforms are present in nucleated and red blood cells, and tissue specific differences in Ro/SSA proteins were identified.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.

SORBS3 is an SH3 domain-containing adaptor protein. The existence of SH3 domains in the SORBS3 protein have a role in its capability to attach to other cytoplasmic molecules and contribute to cystoskeletal organization, cell adhesion and migration, signaling, and gene expression. Various transcript variants encoding different isoforms are known for this gene.

"Epiregulin is part of the EGF family. Epiregulin functions as a ligand of EGFR, as well as a ligand of most members of the ERBB (v-erb-b2 oncogene homolog) family of tyrosine-kinase receptors.Epiregulin is expressed mostly in the placenta and peripheral blood leukocytes and in specific carcinomas of the bladder, lung, kidney and colon. Epiregulin stimulates the proliferation of keratinocytes, hepatocytes, fibroblasts and vascular smooth muscle cells. Epiregulin inhibits the growth of several tumor-derived epithelial cell lines. Human Epiregulin is initially synthesized as a glycosylated 19.0 kDa transmembrane precursor protein, which is processed by proteolytic cleavage to produce a 6.0 kDa mature secreted sequence."

XCL1 is a small cytokine belongs to the XC chemokine family that is also known as lymphotactin. XCL1 is found in high levels in spleen, thymus, intestine and peripheral blood leukocytes, and at lower levels in lung, prostate gland and ovary. Cellular sources for XCL1 include activated thymic and peripheral blood CD8+ T cells. This chemokine attracts T cells. In humans, XCL1 is closely related to XCL2, whose gene is found at the same locus on chromosome 1. XCL1 induces it chemotactic function by binding to a chemokine receptor called XCR1.

LDL is a low-density lipoprotein that transports cholesterol and triglycerides from the liver to peripheral tissues. LDL (like all lipoproteins) facilitates the movement of fats and cholesterol within the water based solution of the blood stream. Each natural LDL particle contains a single Apo B-100 molecule (apolipoprotein B-100 is a protein with 4536 amino acid residues) that circulates the fatty acids and keeps them soluble in the aqueous environment. Additionally, the LDL core is highly-hydrophobic, consisting of linoleate (a polyunsaturated fatty acid) and about 1500 esterified cholesterol molecules. This core is enclosed by a shell of phospholipids and unesterified cholesterol in addition to a single copy of B-100 large protein (514 kD). Even though the LDL particles are approximately 22 nm in diameter and have a mass of about 3 million Daltons, they have a mass and size distribution since the LDL particles contain a varying number of fatty acids. LDL receptors are synthesized and placed in the plasma membrane when a cell requires cholesterol. The LDL receptors scatter freely until they link to clathrin-coated pits. LDL particles in the blood stream attach to these extracellular LDL receptors. The clathrin-coated pits at that time form vesicles that are endocytosed into the cell. Once the clathrin coat is dropped, the vesicles transport the LDL and their receptors to early endosomes, onto late endosomes to lysosomes. At this point the cholesterol esters in the LDL are hydrolysed. The LDL receptors are recovered back to the plasma membrane. Since LDLs convey cholesterol to the arteries and can be retained there by arterial proteoglycans initializing the formation of plaques, increased levels are linked to atherosclerosis, and thus heart attack, stroke, and peripheral vascular disease. And so, cholesterol within LDL lipoproteins is habitually called "bad" cholesterol. This is a misconception since the cholesterol transported on LDL is the same as the one transported on other lipoprotein particles, it is in itself not "bad", rather it is how and where the cholesterol is being transported, and in what amounts ultimately, which causes adverse effects. HDL / LDL ratio can give an indication of risk for arteriosclerosis.

Recombinant Human Lipocalin-2 also called Neutrophil Gelatinase Associated Lipocalin (NGAL) belongs to a family of lipocans which include 25 proteins (including a1-microglobulin and b-lactoglobulin), which are characterized by their ability to bind small lipophilic substances in their hydrophobic core.
They thereby serve as transporters of substances like retinal, biliverdins & prostaglandins. There are indications that NGAL is involved in modulation of the inflammatory response and is found in the plasma of patients after stroke.

Cell Death-Inducing DFFA-Like Effector C (CIDEC) belongs to the cell death-inducing DNA fragmentation factor-like effector family, whose members have significant roles in apoptosis. CIDEC is expressed mainly in adipocytes, intestine, heart, stomach, and weakly in the brain, kidney and liver. CIDEC overexpression in preadipocytes induces apoptosis. CIDEC regulates enlargement of lipid droplets.

Resistin, a product of the RSTN gene, is a peptide hormone belonging to the class of cysteine-rich secreted proteins which is termed the RELM family, and is also described as ADSF (Adipose Tissue- Specific Secretory Factor) and FIZZ3 (Found in Inflammatory Zone). Human resistin contains 108 amino acids as a prepeptide, and its hydrofobic signal peptide is cleaved before its secretion. Resistin circulates in human blood as a dimeric protein consisting of two 92 amino acid polypeptides, which are disulfide-linked via Cys26.
Resistin may be an important link between obesity and insulin resistance. Mouse resistin, specifically produced and secreted by adipocyte, acts on skeletal muscle myocytes, hepatocytes and adipocytes themselves so that it reduces their sensitivity to insulin. Steppan et al. have suggested that resistin suppresses the ability of insulin to stimulate glucose uptake. They have also suggested that resistin is present at elevated levels in blood of obese mice, and is down regulated by fasting and antidiabetic drugs. Way et al., on the other hand, have found that resistin expression is severly suppressed in obesity and is stimulated by several antidiabetic drugs.
Other studies have shown that mouse resistin increases during the differentiation of adipocytes, but it also seems to inhibit adipogenesis. In contrast, the human adipogenic differentiation is likely to be associated with a down regulation of resistin gene expression.