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Introduction: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) and renin-angiotensin system inhibitors (RASi) improve kidney outcomes in people with type 2 diabetes (T2D) . Both drugs favorably affect kidney hemodynamic function which is characterized an acute GFR drop (reflecting reduced glomerular pressure) which, in part, underlies their protective effects. However, the interaction of these drugs on systemic and kidney hemodynamics is unstudied. Methods: During this 4-arm, cross-over, placebo-controlled, double-blind intervention trial, twenty-four T2D patients on metformin and/or sulfonylurea therapy, (age 66±6 years, HbA1c 7.4±0.9%, measured GFR 108±20 mL/min, hypertension treated by beta blockers) were randomized to one-week treatment with empagliflozin (EMPA) 10mg QD, losartan (LOS) 50mg QD, empagliflozin+losartan (EMPA+LOS) and placebo. Fasting GFR was measured by steady-state plasma iohexol clearances. Blood pressure and heart rate (HR) were recorded. Statistical comparisons were done by Friedman test and Wilcoxon rank test correcting for multipele comparisons. Results: Versus placebo, EMPA and LOS monotherapy reduced GFR by 7.0 mL/min (p=0.003) and 7.3 mL/min (p=0.01) respectively, while EMPA+LOS reduced by GFR by 10.7 mL/min (p Conclusion: In people with T2D and preserved kidney function, empagliflozin-losartan therapy induces more pronounced effects on measured GFR and blood pressure versus either of the drugs. These data support their combined use to improve kidney outcomes. Disclosure D.Van raalte: Advisory Panel; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck & Co., Inc., Sanofi, Research Support; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck & Co., Inc., Sanofi. H.L.Heerspink: Consultant; AstraZeneca, Bayer AG, Boehringer Ingelheim International GmbH, Chinook Therapeutics Inc., CSL Behring, Gilead Sciences, Inc., Goldfinch Bio, Inc., Janssen Research & Development, LLC, Mitsubishi Tanabe Pharma Corporation, Mundipharma, Traveere Pharmaceuticals, Research Support; AstraZeneca, Boehringer Ingelheim International GmbH, Novo Nordisk A/S. R.Scholtes: None.

Our objective was to compare renal hemodynamic function between obese youth with and without type 2 diabetes (T2D) and relate these measures to adipose insulin resistance (IR) . We assessed insulin sensitivity and kidney function in obese youth with (n=31, 15.8 ± 1.8 years, BMI 35.6 ± 6.6 kg/m2) , and without (n=20, 15.3 ± 2.1 years, BMI 38.2 ± 7.4 kg/m2) T2D. A hyperglycemic clamp was performed with 20% dextrose to maintain mild hyperglycemia for 240 minutes. Free fatty acids (FFA) were measured at baseline and every minutes during the steady state. FFA suppression (baseline FFA subtracted from steady state FFA) was used to estimate adipose IR. Iohexol and p-aminohippurate clearances were used to measure GFR and renal plasma flow, respectively. Renal hemodynamic parameters were calculated using Gomez equations. FFA suppression was attenuated in youth with T2D compared to obese controls (55.6% vs. 92.1%, p Youth with T2D had impaired FFA suppression compared to obese controls, indicating adipose IR. Impaired FFA suppression was associated with perturbed renal hemodynamics, indicating a potential role for adipose IR in the development of early diabetic kidney disease. Disclosure C.Platnick: None. P.V.Prasad: None. L.Li: None. L.Pyle: None. R.G.Nelson: None. D.Van raalte: Advisory Panel; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck & Co., Inc., Sanofi, Research Support; AstraZeneca, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Merck & Co., Inc., Sanofi. K.J.Nadeau: None. P.Bjornstad: Advisory Panel; AstraZeneca, Bayer AG, Boehringer Ingelheim International GmbH, Horizon Therapeutics plc, LG Chem, Lilly, Novo Nordisk, Consultant; AstraZeneca, Bristol-Myers Squibb Company.

BACKGROUND AND AIMS The gut microbiota has emerged as an important modulator of cardiovascular and renal diseases, including diabetic nephropathy (DN), one of the most common complications caused by diabetes mellitus. Importantly, diabetic patients display a reduction in bacteria producing short chain fatty acids (SCFAs) when compared with healthy individuals. SCFAs are generally associated with beneficial effects on the vascular system, as they help to reduce both oxidative stress and pro-inflammatory stimuli [1]. Although SCFAs help to protect against DN, their mechanisms of action at cell level remain largely unknown. For this reason, we aimed to study the effect of two SCFAs, butyrate and acetate, on human glomerular microvascular endothelial cells (hgMVECs) that represent one of the main components of the glomerular filtration barrier. In case of DN, glomerular endothelium shows multiple signs of dysfunction, such as uncontrolled proliferation [2], mitochondrial fragmentation [3] and monolayer disruption [4]. METHOD hgMVECs have been exposed to different concentrations of butyrate and acetate for 24 h and/or 48 h. After treatment with SCFAs, cells have been collected for qPCR, stained for mitochondrial mass or fixated for immunocytochemistry. For the latter, we have used antibodies for the proliferation marker ki-67 and cell-to-cell junction proteins. To measure the resistance of the endothelial monolayer, electric cell-substrate impedance sensing (ECIS) was used. This system lets a current go over and between cells and the tighter the monolayer, the higher the resistance. For this type of experiment, hgMVECs have been cultured on a specific plate that is located in the ECIS machine throughout the whole experiments (before and after treatment with SCFAs). RESULTS Butyrate decreases the number of ki-67 positive nuclei in a concentration-dependent manner, which implies lower cellular proliferation. On the other hand, at the highest concentration tested (500 uM), butyrate increases mitochondrial mass and elongation, as opposite to acetate, which does not show any effect on mitochondrial mass. These results are also supported by qPCR analysis, where it is possible to observe a decrease of genes involved in mitochondrial fragmentation upon butyrate exposure. MOreover, butyrate increases the resistance of the endothelial monolayer, as we can see in the results of the ECIS experiments. After an initial decrease, butyrate induces a steady increase of the resistance of the monolayer, which does not happen with acetate. We believe that the increase in resistance is due to a higher expression of genes and proteins involved in the formation of tight junctions. For instance, in cells treated with butyrate, gene expression of ve-cadherin, ZO-1, claudin 5 and occludin is upregulated and especially for ve-cadherin this is also observed by immunocytochemistry. CONCLUSION Our results show that in hgMVECs, on the one hand butyrate especially can increase monolayer resistance and influence mitochondrial morphology and possibly its metabolism, while on the other hand it decreases cellular proliferation. Therefore, at cellular level, butyrate can help against several hallmarks of endothelial dysfunction Of DN.