Physiopathogenic Mechanisms Involved in Diabetic Nephropathy, Looking for Prevention and Treatment Solutions

1. Determinations of social, environmental and biological factor implicated in diabetic nephropathy in Ecuador Investigators will study subjects from the general population. Investigators will contact community and religious leaders in order to invite adult subjects from the general population to participate in this study and 10000 persons will be enrolled.

After teaching basic concepts about prevention of diabetic nephropathy in all subjects, investigators will collect demographics data, house conditions and localization (rural, urban or around the cities), number of people that share a home, education level, employment and economical condition, personal health insurance, medical checkup history, toxic habits (alcohol, cigarette abuse of addictive substances) and physical exercises habits. Investigators will collect personal and family antecedent of diabetes mellitus, diabetic nephropathy, hypertension, kidney diseases, diabetes gestational, current treatments and other chronic diseases. Investigators will measure body weight (Kg), height (m) and investigators will calculate body mass index. Investigators will also measure blood pressure, blood glucose, glycosylated hemoglobin, microalbuminuria and proteinuria. Trained personnel will fill out the person's survey. Investigators will supervise and collect data from 2% of the sample. 2. Role of extracellular matrix proteins and growth factors signaling in diabetic nephropathy

1. Systemic and urine studies: proteins involved in diabetic nephropathy pathogenesis as vascular endothelial factor A (VEGF) and extracellular matrix protein as tenascin C (tenascin) concentration will be measured by a commercially available kits in plasma and urine (respectively). Samples will be obtained from diabetics with (n: 20) and without diabetic nephropathy (n: 20) and from non-diabetic subjects (controls) from the general population (n: 2000). Determinations of social, environmental and biological factor will be completed as in aim 1.
2. Kidney tissue studies: investigators will determine the role of protein involved in diabetic nephropathy, VEGF signaling and tenascin in:

I) Paraffin embedded kidney tissue obtained from the sample libraries of pathology laboratories will be studied. Slides from non-diabetics (n: 10) and diabetics with diabetic nephropathy (n: 20) and without diabetic nephropathy (n: 10) will be collected. The role of proteins involved in diabetic nephropathy as VEGF signaling and tenascin will be studied by immunohistochemistry and proximity link assay.

II) Paraffin embedded kidney slides from diabetics with diabetic nephropathy (n: 12), non-diabetic control (n: 6) with primary glomerulopathy as minimal change disease, and diabetic controls without diabetic nephropathy (n: 6), will be studied. Investigators will recruit patients with kidney biopsy indicated, and scheduled to be performed, by their medical doctors. After pathology diagnosis completion, some of the remnant paraffin embedded tissue will be used for this study. The role of proteins involved in diabetic nephropathy, VEGF signaling and tenascin will be studied by immunohistochemistry and proximity link assay. Urine and plasma will be collected prior to the kidney biopsy in order to measure protein concentration of potentially useful biomarkers of diabetic nephropathy; VEGF and tenascin levels will be quantified. Patients will be informed and signed consent will be required.