Abstract P254: Sex Differences In Angiotensin Ii-induced Hypertension In Mice With Proximal Tubule-specific Deletion Of Mitochondrial Protein Sirtuin 3 In The Kidney

The development of Angiotensin II (Ang II)-induced hypertension is associated with mitochondrial dysfunction and kidney injury. Sirtuin 3 (SIRT3), a key mitochondrial protein, plays an important role in maintaining mitochondrial homeostasis. However, it remains unknown whether deletion of SIRT3 in the proximal tubules will alter the pressor and renal responses to Ang II in sex-different manners. In the present study, adult male, and female wild-type (WT) and mutant mice with proximal tubule-specific knockout of SIRT3, PT- Sirt3 -/- , were infused with or without a slow pressor dose of Ang II via an osmotic minipump (0.5 mg/kg/day, i.p.), supplemented with a 2% NaCI diet or losartan, 20 mg/kg/day, for 2 weeks. Systolic (SBP), diastolic (DBP), and mean arterial blood (MAP) pressure were determined using the tail-cuff method, whereas 24 hr. urinary sodium and potassium excretion were determined using a metabolic cage. Serum and urine creatinine were measured using colorimetric assays, whereas glomerular and tubulointerstitial injury was evaluated by Masson’s Trichrome staining. Basal SBP levels were lower in PT- Sirt3 -/- than in WT mice (SBP-WT: 112 ± 2 vs. SBP-PT- Sirt3 -/- : 93 ± 2 mmHg, P <0,01). The magnitude of Ang II-induced hypertension was similar between WT and PT- Sirt3 -/- mice with or without losartan treatment. Serum creatinine levels and urinary creatinine excretion were higher in PT- Sirt3 -/- mice than in WT mice ( P <0.05), but without significant sex differences in response to Ang II infusion or losartan treatment. Differences were found only in female WT and PT- Sirt3 -/- mice with lower 24 hr. urine and urinary creatinine excretion in response to Ang II infusion or losartan. Losartan significantly increased 24 hr. urinary potassium and chloride excretion in Ang II-infused male and female PT- Sirt3 -/- mice ( P <0.01). Finally, Ang II-infused PT- Sirt3 -/- mice showed significant renal cortical tubulointerstitial fibrotic responses ( P <0.05), but not glomerular fibrotic responses. We conclude that basal blood pressure is lower in male and female PT- Sirt3 -/- mice and that Ang II induces similar hypertensive and renal fibrotic responses in male and female PT- Sirt3 -/- mice without significant sex differences.

Advanced Skeletal Muscle Mass Reduction (Sarcopenia) Secondary to Neuromuscular Disease

We describe a young male patient chronically on a ventilator secondary to decreased mobility from amyotrophic lateral sclerosis (ALS). He had both a tracheostomy for breathing and percutaneous endoscopic gastrostomy (PEG) for feeding. Using 24-hour urinary creatinine excretion data, we calculated an estimate of skeletal muscle (SM) mass. SM mass was indexed to height and weight to obtain the SM index. The SM index is used as a determinant to define sarcopenia. From the data, we found that this patient had the smallest SM index ever recorded at 2.2 kg/m2, consistent with extremely advanced sarcopenia. As a comparison, “severe” sarcopenia in a male is defined as a SM index≤8.5 kg/m2. This method can be used in ICU patients to evaluate for sarcopenia which is a predictive marker for mortality.

Weight Adjusted Urinary Creatinine Excretion Predicts Transplant Outcomes in Adult Patients with Acute Myeloid Leukemia in Complete Remission

Background: Sarcopenia, the loss of muscle mass, has been recognized as a prognostic factor for cancer patients. For example, low body mass index (BMI) was reported to be a risk of poor overall survival (OS) among allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. However, low BMI was not associated with high non-relapse mortality (NRM) rate, and BMI may not directly reflect the physical condition. (Bone Marrow Transplant. 2014;49:1505-12). To evaluate the clinical impact of the muscle volume on the prognosis of allo-HSCT recipients, other biomarkers that directly reflect muscle mass may be warranted. Urinary creatinine excretion (UCE) has been reported to estimate muscle mass and have prognostic value for kidney transplant patients (Transplantation. 2008;86:391-8.). There is no report to evaluate clinical impact of UCE on the prognosis of allo-HSCT recipients. Therefore, we retrospectively analyzed the association between pre-transplant UCE and the transplant outcomes. Methods: We included 173 adult patients with acute myeloid leukemia (AML) in complete remission (CR) who underwent first allo-HSCT from 2006 to 2017 at our institute and measured UCE before allo-HSCT. Concerned the possibility of urine storage failure, two patients with low total daily urine volume (<0.5L/day) were excluded from this analysis. Therefore, we investigated the remaining 171 patients. In order to correct the physical disparities of individual patients, we evaluated the clinical impact of weight adjusted UCE (WA-UCE) ,i.e UCE / body weight [μmol/kg/day] (Intensive Care Med. 2018;44:1699-708.). We used receiver operating characteristics curve in order to determine the cutoff value of the WA-UCE and classified the patients into the high and low WA-UCE group. We evaluated transplant outcomes such as OS, progression-free survival (PFS), NRM, and cumulative incidence of relapse (CIR) between two groups. Results: The median age at allo-HSCT was 52 (range, 18-73) and there were more male patients (n=111) than female patients (n=60). Regarding cytogenetic risk, 15 (9.1%), 112 (65.8%), and 38 (23.0%) were categorized as favorable, intermediate, and poor risk, respectively (There were five patients without cytogenetic data). The median follow-up period of survivors was 704 (range, 9 to 3,857) days. We defined the cutoff value of the weight adjusted UCE as 148 μmol/kg/day in male and 128 μmol/kg/day in female. Among 171 patients, 90 patients (male = 59, female = 31) were in the high WA-UCE group and 81 patients (male = 52, female = 29) were in the low WA-UCE group. We found no significant differences between two groups in terms of the number of relapse before allo-HSCT, cytogenetic risks, conditioning regimens, hematopoietic cell transplantation comorbidity index, donor-recipient HLA matching, donor source, or estimated glomerular filtration rate. On the other hand, patient's age at allo-HSCT was significantly younger (low vs. high WA-UCE group: median, 53 [range, 18 - 73] vs. 48 [range, 19 - 68] years, P = 0.02) and BMI was lower (low vs. high WA-UCE group: median, 22.3 [range, 15.4 - 38.8] vs. 21.9 [range, 15.4 - 29.3] kg/m2, P = 0.003) in high WA-UCE group. In univariate analysis, we observed a significant difference in OS, PFS, and NRM between two groups (low vs. high WA-UCE group: 1-year OS, 60.1% vs. 80.9%, P < 0.01; 1-year PFS, 54.1% vs. 70.9%, P = 0.02; 1-year NRM, 24.8% vs. 12.3%, P = 0.02) (Figure1). On the other hand, there was no significant difference in 1-year CIR between two groups (low vs. high WA-UCE group: 21.1% vs. 16.8%, P = 0.63). In our cohort, the low BMI (< 18.5 kg/m2) was not significantly associated with OS, PFS, CIR, and NRM (low vs. high BMI group: 1-year OS, 77.6% vs. 69.9%, P = 0.51; 1-year PFS, 74.1% vs. 60.9%, P = 0.45; 1-year CIR, 14.8% vs. 19.5%, P = 0.02, 1-year NRM, 11.1% vs. 19.5%, P = 0.70) In multivariate analysis, the low WA-UCE was an independent risk factor for OS (Hazard ratio (HR) [95% confidence interval (CI)]; 2.29 [1.38 - 3.80], P < 0.01), PFS (HR [95% CI]; 1.76 [1.11 - 2.79], P = 0.02), and NRM (HR [95% CI]; 2.22 [1.13 - 4.36], P = 0.02) (table1). Conclusion: In allo-HSCT adult recipients with AML in CR, low WA-UCE before transplantation was associated with poor prognosis, which related to high NRM within 1 year. WA-UCE can be an independent, objective, simple, and reliable biomarker for evaluating muscle mass and predicting transplant outcome. Disclosures No relevant conflicts of interest to declare.

Impact of Dietary Protein intake, Lean Body Mass percentage, Body Mass Index, Physical activity on Urinary Creatine and Urinary Creatinine excretion in a TeamSport

Background: Creatine and Creatinine plays a role in muscle function. Urinary creatine and urinary creatinine concentration was measured in order to see significance in monitoring athlete and athlete’s performance. Objective: Evaluate association of dietary protein intake, Lean Body Mass (LBM) percentage, Body Mass Index (BMI) and physical activity on urinary creatine, urinary creatinine concentration in different team sports [cricket players (C), basketball players (B) and football players (F)]. Methodology: A total of 62 players from different team sports - C (n-20), B (n-17) and F (n-25) age of 18-30 years participated. Post training urine samples was analyzed. Using Jaffe's reaction, urinary creatinine was obtained and Urinary creatine is obtained by difference in the creatinine present before and after heating with acid solution. 24 hour dietary recall was taken to find athletes protein intake. LBM were taken using Body Impedence Analysis (BIA machine). Data were analysed using SPSS (Statistical Package for Social Sciences Version 16.0). Findings: Pearson bivariate correlation (2-tailed) was used to find the relationship between BMI, LBM, total dietary protein intake per day, dietary protein, duration of practice with urine creatinine and creatine level. Positive correlation between urinary creatine and total dietary protein intake per day, dietary protein according to body weight per day was found (p<0.001), (p<0.005) respectively. Negative correlation between urinary creatinine and dietary protein according to body weight per day and duration of practice per day was found (p<0.001), (p<0.005) respectively. Urinary creatine mean (SD) values- C group 78.63 ± 27.17, B group 102.65 ± 38 and F group 169.60±41.58. Urinary creatinine mean (SD) values- C group 46.60 ± 37.23,B group 84.88 ± 48.27 and F group 70.40±44.083. Conclusion & Significance: Significant increase was seen in urinary creatine excretion with respect to dietary protein per day, dietary protein according to body weight per day. Urinary creatine excretion is more in football players followed by basketball players. Significant decline was seen in urinary creatinine excretion with respect to increase dietary protein according to body weight per day and increase duration of practice. Urinary Creatine excretion is more in basketball players followed by football players Urinary creatine and urinary creatinine excretion depends on sports-type, duration of sports and protein consumption.