When the amount of proteins excreted in the urine exceeds the livers ability to compensate, fewer proteins are detected in the blood – in particular albumin, which makes up the majority of circulating proteins. With decreased proteins in the blood, there is a decrease in the oncotic pressure of the blood. This results in edema, as the oncotic pressure in tissue remains the same. Although decreased intravascular oncotic (i.e. osmotic) pressure partially explains the patients edema, more recent studies have shown that extensive sodium retention in the distal nephron (collecting duct) is the predominant cause of water retention and edema in the nephrotic syndrome. This is worsened by the secretion of the hormone aldosterone by the adrenal gland, which is secreted in response to the decrease in circulating blood and causes sodium and water retention. Hyperlipidemia is thought to be a result of the increased activity of the liver. : 549

Nephritic syndrome
The nephritic syndrome is characterised by blood in the urine (especially Red blood cell casts with dysmorphic red blood cells) and a decrease in the amount of urine in the presence of hypertension. In this syndrome, inflammatory damage to cells lining the glomerulus are thought to result in destruction of the epithelial barrier, leading to blood being found in the urine. At the same time, reactive changes, e.g. proliferation of mesangial cells, may result in a decrease in kidney blood flow, resulting in a decrease in the production of urine.
Nrf2 is decreased in FRDA cells. PTC-743 (formerly EPI-743) is being developed by PTC Therapeutics. PTC-743 is a para-benzoquinone and targets the NAD(P)H dehydrogenase (quinone 1) (NQO1) enzyme to increase the biosynthesis of glutathione. Retrotope is advancing RT001. RT001 is a deuterated synthetic homologue of ethyl linoleate, an essential omega-6 polyunsaturated fatty acid which is one of the major components of lipid membranes, particularly in mitochondria. Oxidation  damage might be reduced if the polyunsaturated fatty acids in the lipids were made more rigid and less susceptible to oxidation by the replacement of hydrogen atoms with the heavy hydrogen isotope deuterium. Modulation of frataxin controlled metabolic pathways
Dimethyl fumarate has been shown to increase frataxin levels in FRDA cells, mouse models, and humans. DMF showed an 85% increase in frataxin expression over 3 months in multiple sclerosis . Frataxin replacements or stabilizers
EPO mimetics are orally available peptide imitations of erythropoietin. They are small molecules erythropoietin receptor agonists designed to activate the tissue-protective erythropoietin receptor. Etravirine, an antiviral drug used to treat HIV, was found in a drug repositioning screening to increase frataxin levels in peripheral cells. Fratagene Therapeutics is developing a small molecule called RNF126 to inhibit an enzyme which degrades frataxin. Increase frataxin gene expression
Resveratrol might improve mitochondrial function. Nicotinamide (vitamin B3) was found effective in preclinical FRDA models and well tolerated. An RNA-based approach might unsilence the FXN gene and increase the expression of frataxin. Non-coding RNA (ncRNA) could be responsible for directing the localized epigenetic silencing of the FXN gene.