P0681TIMP-1 DEFICIENCY DAMPENS RENAL GALECTIN-3 RESPONSE IN DIABETES

Background and Aims Overexpression of tissue inhibitors of metalloproteases (TIMPs) are a hallmark of renal fibrosis, and elevated TIMP-1 has been reported in experimental and human diabetes. Also, renal galectin-3 (Lgals3) overproduction might link macrophages to fibrosis progression. However, the possible association of renal Lgals3 with TIMP-1 in diabetes is still unclear. Thus, we investigated nephropathy and renal Lgals3 in type-1 diabetic wild type and TIMP-1 knockout (KO) mice. Method Type-1 diabetes was induced in 6 week-old male TIMP-1 KO (DM KO, n=7) and wild type (DM, n=6) mice with daily intraperitoneal streptozotocin (50 mg/kg/day) injections for 5 consecutive days. Non-diabetic controls (CTL, n=5) were injected with vehicle. Fasting blood glucose was monitored, and after 8 weeks kidneys were analyzed for histology and mRNA expression. Results Both diabetic groups developed similar hyperglycemia (CTL: 6±2, DM: 29±5, DM KO: 33±7 mmol/l, p<0.01). However, serum creatinine was elevated only in wild type diabetic mice (CTL: 9±2, DM: 47±28, DM KO: 11±2 ug/dl, p<0.001). Histology revealed significant tubular damage in DM mice (score: CTL: 0.4±0.1, DM: 2.3±0.2, DM KO: 1.6±0.2, p<0.05), accompanied by 10-fold lipocalin-2 (CTL: 1.0±0.3, DM: 10.9±6.2, DM KO: 3.3±1.7, p<0.05) and 2-fold collagen-1 overexpression (CTL: 1.0±0.2, DM: 1.9±0.7, DM KO: 1.2±0.4, p<0.05), practically absent in diabetic KO kidneys. Similarly, TIMP-1 deficiency was associated with twofold decrease in renal Lgal3 (CTL: 1.0±0.6, DM: 2.0±1.1, DM KO: 0.8±0.3, p<0.05) and tenfold decrease in CCL2 expression levels (CTL: 1.0±0.3, DM: 20.2±4.2, DM KO: 2.3±1.5, p<0.01) as compared to DM. Conclusion In our model of type-1 diabetes, TIMP-1 deficiency attenuated the development of renal fibrotic and inflammatory response by reducing galectin-3 and CCL2 (MCP-1), preserved tubular integrity and renal function. This might implicate TIMP-1 to be a possible therapeutic target in the future.

Revisiting the Ancylostoma caninum secretome provides new information on hookworm-host interactions

ABSTRACTHookworm infection is a major tropical parasitic disease affecting almost 500 million people worldwide. These soil-transmitted helminths can survive for many years in the intestine of the host, where they feed on blood, causing iron deficiency anaemia and other complications. To avoid the host’s immune response the parasite releases excretory/secretory products (ESPs), a complex mixture of glycans, lipids and proteins that represent the major host-parasite interface. Using a combination of separation techniques such as SDS-PAGE and OFFGEL electrophoresis, in combination with state-of-the-art mass spectrometry we have reanalysed the dog hookworm, Ancylostoma caninum, ESPs (AcES). We identified 315 proteins present in the AcES, compared with just 105 identified in previous studies. The most highly represented family of proteins is the SCP/TAPs (90 of the 315 proteins), and the most abundant constituents of AcES are homologues of the tissue inhibitors of metalloproteases (TIMP) family. We identified putative vaccine candidates and proteins that could have immunomodulatory effects for treating inflammatory diseases. This study provides novel information about the proteins involved in host-hookworm interactions, and constitutes a comprehensive dataset for the development of vaccines and the discovery of new immunoregulatory biologics.

MMP-14 is necessary but not sufficient for invasion of three-dimensional collagen by human muscle satellite cells

The twenty-five known matrix metalloproteases (MMPs) and their endogenous inhibitors, tissue inhibitors of metalloproteases (TIMPs), mediate cell invasion through the extracellular matrix (ECM). In a comparative three-dimensional assay, we analyzed human and mouse satellite cells' competence to invade an artificial ECM (collagen I). We identified a single MMP that 1) is expressed by human muscle satellite cells; 2) is induced at the mRNA/protein level by adhesion to collagen I; and 3) is necessary for invasion into a collagen I matrix. Interestingly, murine satellite cells neither express this MMP, nor invade the collagen matrix. However, exogenous human MMP-14 is not sufficient to induce invasion of a collagen matrix by murine cells, emphasizing species differences.