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Singh, Ravinder J.

https://orcid.org/0000-0003-4538-6544

Mayo Clinic

Mayo Clinic

Citations 93

Challenges in Translating Clinical Metabolomics Data Sets from the Bench to the Bedside
Ulmer, Candice Z. , Hines, Jolaine, Maus, Anthony , Singh, Ravinder J.

Clinical Chemistry | October 6, 2021 | Volume: 67 | Issue: 12 | Pages: 1581-1583

10.1093/clinchem/hvab210 Get It

Initiation of Gender-Affirming Testosterone Therapy in a Lactating Transgender Man
Oberhelman, Sara S. , Chang, Alice Y. , González, César A. , Braith, Andrew, Lteif, Aida, Oberhelman, Sara , Chang, Alice, Gonzalez, Cesar, Gonzalez, Cesar , Singh, Ravinder J.

Journal of Human Lactation | September 7, 2021 | Volume: 38 | Issue: 2 | Pages: 339-343

10.1177/08903344211037646 Get It

Introduction: Transgender and gender diverse individuals may choose to provide their infants with human milk. Lactating transgender men may experience gender dysphoria and desire to initiate or reinitiate gender-affirming testosterone therapy. However, there is limited safety data regarding use of testosterone during lactation. Main Issue: A 30-year-old G2P2 transgender man with gender dysphoria sought to initiate gender-affirming testosterone therapy while lactating. Management: Subcutaneous testosterone was self-administered beginning at 13 months post-partum. We prospectively collected data on circulating testosterone concentrations in parent serum, milk, and infant serum over 5 months until the infant self-weaned. The infant was monitored for growth and development at routine pediatric outpatient appointments. Parent serum testosterone concentrations rose with the initiation of testosterone therapy, reaching therapeutic concentrations by Day 14. Milk testosterone concentrations also increased with a maximum concentration of 35.9 ng/dl when the lactating parent was on a dose of 80 mg subcutaneous testosterone cypionate weekly. The calculated milk/plasma ratio remained under 1.0 and the calculated relative infant dose remained under 1%. The infant had no observable side effects, and his serum testosterone concentrations remained undetectable throughout the study period. Conclusion: This is the first study with data regarding human milk and infant serum testosterone concentrations during the initiation of gender-affirming testosterone therapy in a lactating individual. This evidence can help families and clinicians with decisions regarding lactation and testosterone use.
Fisetin for COVID ‐19 in skilled nursing facilities: Senolytic trials in the COVID era
Verdoorn, Brandon P. , Evans, Tamara K., Hanson, Gregory J. , Zhu, Yi , Prata, Larissa , Pignolo, Robert J. , Atkinson, Elizabeth J. , Wissler-Gerdes, Erin O., Kuchel, George A. , Mannick, Joan B. , Rizza, Stacey A. , Musi, Nicolas , Lipsitz, Lewis A. , Yung, Raymond , McCarthy, Teresa , Puskarich, Michael A. , Niedernhofer, Laura J. , Kirkland, James L. , Gerdes, Erin O. Wissler , Langhi Prata, Larissa G P, Sorenson, Matthew, Tchkonia, Tamara, Wissler Gerdes, Erin O , Prata, Larissa G P Langhi , Niedernhofer, Laura J , Kuchel, George A , Zhu, Yi , Hanson, Gregory J., Kritchevsky, Stephen B. , Khosla, Sundeep , Walston, Jeremy D , Kiel, Douglas P. , LeBrasseur, Nathan K. , Singh, Ravinder J. , Robbins, Paul D. , Sorenson, Matthew , Tchkonia, Tamar

Journal of the American Geriatrics Society | August 10, 2021 | Volume: 69 | Issue: 11 | Pages: 3023-3033

10.1111/jgs.17416 Get It

Abstract The burden of senescent cells (SnCs), which do not divide but are metabolically active and resistant to death by apoptosis, is increased in older adults and those with chronic diseases. These individuals are also at the greatest risk for morbidity and mortality from SARS‐CoV‐2 infection. SARS‐CoV‐2 complications include cytokine storm and multiorgan failure mediated by the same factors as often produced by SnCs through their senescence‐associated secretory phenotype (SASP). The SASP can be amplified by infection‐related pathogen‐associated molecular profile factors. Senolytic agents, such as Fisetin, selectively eliminate SnCs and delay, prevent, or alleviate multiple disorders in aged experimental animals and animal models of human chronic diseases, including obesity, diabetes, and respiratory diseases. Senolytics are now in clinical trials for multiple conditions linked to SnCs, including frailty; obesity/diabetes; osteoporosis; and cardiovascular, kidney, and lung diseases, which are also risk factors for SARS‐CoV‐2 morbidity and mortality. A clinical trial is underway to test if senolytics decrease SARS‐CoV‐2 progression and morbidity in hospitalized older adults. We describe here a National Institutes of Health‐funded, multicenter, placebo‐controlled clinical trial of Fisetin for older adult skilled nursing facility (SNF) residents who have been, or become, SARS‐CoV‐2 rtPCR‐positive, including the rationale for targeting fundamental aging mechanisms in such patients. We consider logistic challenges of conducting trials in long‐term care settings in the SARS‐CoV‐2 era, including restricted access, consent procedures, methods for obtaining biospecimens and clinical data, staffing, investigational product administration issues, and potential solutions for these challenges. We propose developing a national network of SNFs engaged in interventional clinical trials.
Renal interstitial corticosterone and 11‐dehydrocorticosterone in conscious rats
Usa, Kristie , Netzel, Brian C., Liu, Yong , Singh, Ravinder J. , Liang, Mingyu

The FASEB Journal | June 21, 2021 | Volume: 21 | Issue: 6 | Pages: No page available

10.1096/fasebj.21.6.a893-c Get It

Vitamin D3 Dose Requirement That Raises 25-Hydroxyvitamin D to Desirable Level in Overweight and Obese Elderly
Bacha, Dania S. , Rahme, Maya , Al‐Shaar, Laila , Halaby, Georges, Mahfoud, Ziyad , Habib, Robert, Arabi, Asma , Fuleihan, Ghada El‐Hajj , El-Hajj Fuleihan, Ghada , Baddoura, Rafic , Singh, Ravinder J.

The Journal of Clinical Endocrinology & Metabolism | May 6, 2021 | Volume: 106 | Issue: 9 | Pages: e3644-e3654

10.1210/clinem/dgab296 Get It

Abstract Context Guidelines for the dosage of vitamin D supplementation vary widely globally. Objective To investigate the impact of 2 vitamin D doses, bracketed between the IOM recommended dietary allowance (RDA) and the upper tolerable limit, on vitamin D nutritional status in elderly individuals. Methods This post hoc analysis of data collected from a 12-month, double-blind, randomized control trial included 221 ambulatory participants (≥ 65 years) with a mean BMI of 30.2 kg/m2 and a mean baseline serum 25-hydroxyvitamin D [25(OH)D] level of 20.4 ± 7.4 ng/mL, who were recruited from 3 outpatient centers in Lebanon. All participants received 1000 mg of elemental calcium daily from calcium citrate plus the daily equivalent of either 600 IU or 3750 IU of vitamin D3. Results Mean 25(OH)D level at 12 months was 26.0 ng/mL with low dose and 36.0 ng/mL with high dose vitamin D3. The proportion of participants reaching a value ≥ 20 ng/mL was 86% in the low dose, and 99% in the high dose arms, with no gender differences. The increment of 25(OH)D per 100 IU/day was 1 ng/mL with the low dose, and 0.41 ng/mL with the high dose. Serum 25(OH)D levels at 1 year were highly variable in both treatment arms. Baseline 25(OH)D level and vitamin D dose—but not age, BMI, gender, or season—were significant predictors of serum 25(OH)D level post-intervention. Conclusion The IOM Recommended Dietary Allowance (RDA) of 600 IU/day does not bring 97.5% of ambulatory elderly individuals above the desirable threshold of 20 ng/mL. Country-specific RDAs are best derived taking into account the observed variability and predictors of achieved 25(OH)D levels.
1α,25-Dihydroxyvitamin D3 Encapsulated in Nanoparticles Prevents Venous Neointimal Hyperplasia and Stenosis in Porcine Arteriovenous Fistulas
Singh, Avishek , Cai, Chuanqi , Kilari, Sreenivasulu , Zhao, Chenglei , Simeon, Michael L. , Takahashi, Edwin A. , Kong, Hyunjoon , Macedo, Thanila A. , Misra, Sanjay , Singh, Avishek K, Takahashi, Edwin, Macedo, Thanila, Misra, Sanjay , Kong, Hyunjoon , Takahashi, Edwin A , Edelman, Elazer R. , Singh, Ravinder J. , Urban, Matthew W. , Kumar, Rajiv , Kilari, Sreenivasulu

Journal of the American Society of Nephrology | February 24, 2021 | Volume: 32 | Issue: 4 | Pages: 866-885

10.1681/asn.2020060832 Get It

Significance Statement Expression of immediate early response gene X-1 ( Iex-1 ), also known as Ier-3, is increased in venous neointimal hyperplasia (VNH) and stenosis in hemodialysis arteriovenous fistulas (AVF). In a porcine model, 1α,25(OH) 2 D 3 , an inhibitor of Ier3, reduced VNH/stenosis formation. The 1α,25(OH) 2 D 3 released in the perivascular AVF space from poly(lactic-co-glycolic acid) nanoparticles embedded in a Pluronic F127 hydrogel (1,25 NP) reduced Ier3 gene and protein expression, MCP-1, CD68, HIF-1α, and VEGF-A immunostaining. Concomitantly, blood flow, lumen area, pulse wave velocity, and Young’s modulus increased, and neointima area, peak systolic velocity, and wall shear stress decreased in 1,25 NP–treated vessels. RNA sequencing analysis identified 242 genes involved in inflammatory and apoptotic pathways that had decreased expression in 1,25 NP vessels. Background Few therapies prevent venous neointimal hyperplasia (VNH) and venous stenosis (VS) formation in arteriovenous fistulas (AVF). Expression of the immediate early response gene X-1 ( Iex-1 ), also known as Ier3, is associated with VNH and stenosis in murine AVFs. The study aimed to determine if local release of Ier3 long-acting inhibitor 1α,25(OH) 2 D 3 from poly(lactic-co-glycolic acid) (PLGA) nanoparticles embedded in a thermosensitive Pluronic F127 hydrogel (1,25 NP) could affect VNH/VS formation in a large animal model. Methods Immediately after AVF creation in a porcine model of renal failure, 1,25 NP or vehicle control was injected into the adventitia space of AVF outflow veins. Scanning electron microscopy and dynamic light scattering characterized drug and control nanoparticles. Animals were sacrificed 3 and 28 days later for gene expression, immunohistologic, magnetic resonance imaging and angiography, and ultrasound analyses. Whole transcriptome RNA sequencing with differential gene expression analysis was performed on outflow veins of AVF. Results Encapsulation of 1α,25(OH) 2 D 3 in PLGA nanoparticles formed nanoparticles of uniform size that were similar to nanoparticles without 1α,25(OH) 2 D 3 . The 1,25 NP–treated AVFs exhibited lower VNH/VS, Ier3 gene expression, and IER-3, MCP-1, CD68, HIF-1α, and VEGF-A immunostaining, fibrosis, and proliferation. Blood flow and lumen area increased significantly, whereas peak systolic velocity and wall shear stress decreased. Treatment increased Young’s modulus and correlated with histologic assessment of fibrosis and with no evidence of vascular calcification. RNA sequencing analysis showed changes in the expression of genes associated with inflammatory, TGFβ1, and apoptotic pathways. Conclusions Local release of 1,25 NP improves AVF flow and hemodynamics, and reduces stenosis in association with reduction in inflammation, apoptosis, and fibrosis in a porcine model of arteriovenous fistula.
Steroidogenesis in patients with adrenal incidentalomas: Extended steroid profile measured by liquid chromatography‐mass spectrometry after ACTH stimulation and dexamethasone suppression
Huayllas, Martha Katherine Paniagua , Gallagher, John C. , Netzel, Brian C., Kater, Cláudio E. , Huayllas, Martha K P , Smith, Lynette M. , Singh, Ravinder J.

Clinical Endocrinology | February 18, 2021 | Volume: 95 | Issue: 1 | Pages: 29-40

10.1111/cen.14445 Get It

AbstractObjectiveDescribe the secretion and profile of adrenal steroids in patients with adrenal incidentalomas compared to control subjects.Design, Setting and ParticipantsA prospective study, 73 patients with adrenal incidentalomas, 21 bilateral and 52 unilateral and 34 matched controls in University Hospital.MethodsCollect fasting blood sample before and 60 min after ACTH test (250 µg IV). One week later, perform overnight 1 mg dexamethasone test. The following steroids were measured by liquid chromatography‐mass spectrometry (LC‐MS): pregnenolone, 17‐OH pregnenolone, 17‐OH progesterone, 11‐deoxycorticosterone, 11‐deoxyortisol, 21‐deoxycortisol, corticosterone, cortisol, androstenedione and aldosterone.ResultsMean baseline serum cortisol was higher in incidentalomas, bilateral 361 ± 124, (range 143–665) nmol/L,(p < .0001), unilateral 268 ± 89 3.2 (range 98–507) nmol/L (p < .019) compared to controls 207 ± 100 (range 72–502) nmol/L. ACTH stimulation showed significantly higher levels in bilateral and unilateral cases compared to controls. After dexamethasone, mean serum cortisol levels suppressed in bilaterals 89 ± 69 (range 30–3) nmol/L (p < .0001), 58 ± 52 (range 16–323) nmol/L in unilateral (p < .01) compared to 26 ± 9 (range 7–46) nmol/L in controls. Mean baseline serum corticosterone was higher in bilateral 9.3 ± 4.8 (range 2.4–18.4) nmol/L (p < .005) and unilateral 7.3 ± 5.7 (range 0.1–30.3) nmol/L (p < .01) compared to controls 4.2 ± 2.4 (range 1.1–10.2) nmol/L, after ACTH stimulation significantly increased to higher levels in bilateral (p < .0002) and unilateral cases (p < .044) compared to controls. After dexamethasone, mean levels were 2.5 ± 2.6 (range 0.5–12.5) nmol/L in bilateral (p < .0006), 1.5 ± 1.6 (range 0.3–9.3) nmol/L in unilateral (p < .09) and 0.75 ± 0.46 (range 0.1–2.1) nmol/L in controls. Mean baseline serum 11‐deoxycorticosterone (DOC) was higher in bilaterals 0.32 ± 0.23 (range 0.08–1.1) nmol/L (p < .03) compared to controls 0.15 ± 0.21 (range 0.08–1.1) nmol/L. ACTH stimulation increased levels to 3.27 ± 1.72 (range 0.5–7.4) nmol/L in bilateral cases compared to controls 1.369 ± 1.53 (range 0.1–7.1) nmol/L (p < .0001). Dexamethasone decreased levels to baseline (p ns). There were significant differences in serum 21‐deoxycortisol (p < .0002) and serum pregnenolone (p < .004) only after ACTH stimulation.ConclusionsThere is increased activity in several steroid biosynthesis pathways and higher steroid levels in bilateral compared to unilateral cases and evidence of hypercortisolism in 30% unilateral and 62% of bilateral incidentalomas.
New Cutoffs for the Biochemical Diagnosis of Adrenal Insufficiency after ACTH Stimulation using Specific Cortisol Assays
Javorsky, Bradley R. , Raff, Hershel , Carroll, Ty B , Colón-Franco, Jessica M , Findling, James W. , Carroll, Ty B , Singh, Ravinder Jit, Carroll, Ty B , Algeciras‐Schimnich, Alicia , Singh, Ravinder J.

Journal of the Endocrine Society | February 18, 2021 | Volume: 5 | Issue: 4 | Pages: No page available

10.1210/jendso/bvab022 Get It

Abstract Context The normal cortisol response 30 or 60 minutes after cosyntropin (ACTH[1–24]) is considered to be ≥18 μg/dL (500 nmol/L). This threshold is based on older serum cortisol assays. Specific monoclonal antibody immunoassays or LC-MS/MS may have lower thresholds for a normal response. Objective To calculate serum cortisol cutoff values for adrenocorticotropic hormone (ACTH) stimulation testing with newer specific cortisol assays. Methods Retrospective analysis of ACTH stimulation tests performed in ambulatory and hospitalized patients suspected of adrenal insufficiency (AI). Serum samples were assayed for cortisol in parallel using Elecsys I and Elecsys II immunoassays, and when volume was available, by Access immunoassay and LC-MS/MS. Results A total of 110 patients were evaluated. Using 18 μg/dL as the cortisol cutoff after ACTH stimulation, 14.5%, 29%, 22.4%, and 32% of patients had a biochemical diagnosis of AI using the Elecsys I, Elecsys II, Access, and LC-MS/MS assays, respectively. Deming regressions of serum cortisol were used to calculate new cortisol cutoffs based on the Elecsys I cutoff of 18 μg/dL. For 30-minute values, new cutoffs were 14.6 μg/dL for Elecsys II, 14.8 μg/dL for Access, and 14.5 μg/dL for LC-MS/MS. Baseline cortisol &lt;2 μg/dL was predictive of subnormal stimulated cortisol values. Conclusion To reduce false positive ACTH stimulation testing, we recommend a new serum cortisol cutoff of 14 to 15 μg/dL depending on the assay used (instead of the historical value of 18 μg/dL with older polyclonal antibody assays). Clinicians should be aware of the new cutoffs for the assays available to them when evaluating patients for AI.
Chemical Characterization and Quantification of Circulating Intact PTH and PTH Fragments by High-Resolution Mass Spectrometry in Chronic Renal Failure
Kritmetapak, Kittrawee , Losbanos, Louis, Hines, Jolaine M., O’Grady, Katherine , Ulmer, Candice Z. , Vesper, Hubert W. , Losbanos, Louis A, O'Grady, Katherine L, Enders, Felicity T, Enders, Felicity , Singh, Ravinder J. , Kumar, Rajiv

Clinical Chemistry | January 20, 2021 | Volume: 67 | Issue: 6 | Pages: 843-853

10.1093/clinchem/hvab013 Get It

Abstract Background The precise concentrations of full-length parathyroid hormone (PTH1-84) and the identity and concentrations of PTH fragments in patients with various stages of chronic renal failure are unknown. Methods We developed a liquid chromatography-high resolution mass spectrometry (LC-HRMS) method to characterize and quantify PTH1-84 and PTH fragments in serum of 221 patients with progressive renal dysfunction. Following capture by matrix-bound amino-terminal or carboxyl-terminal region-specific antibodies and elution from matrix, PTH1-84 and PTH fragments were identified and quantitated using LC-HRMS. PTH was simultaneously measured using an intact PTH (iPTH) immunoassay. Results Full-length PTH1-84 and 8 PTH fragments (PTH28-84, 34-77, 34-84, 37-77, 37-84, 38-77, 38-84, and 45-84) were unequivocally identified and were shown to increase significantly when an eGFR declined to ≤17-23 mL/min/1.73m2. Serum concentrations of PTH1-84 were similar when measured by LC-HRMS following capture by amino-terminal or carboxyl-terminal immunocapture methods. In patients with an eGFR of &lt;30 mL/min/1.73 m2, serum PTH concentrations measured using LC-HRMS were significantly lower than PTH measured using an iPTH immunoassay. PTH7-84 and oxidized forms of PTH1-84 were below the limit of detection (30 and 50 pg/mL, respectively). Conclusions LC-HRMS identifies circulating PTH1-84, carboxyl-terminal PTH fragments, and mid-region PTH fragments, in patients with progressive renal failure. Serum PTH1-84 and its fragments markedly rise when an eGFR decreases to ≤17-23 mL/min/1.73 m2. PTH concentrations measured using LC-HRMS tend to be lower than those measured using an iPTH immunoassay, particularly in severe chronic renal failure. Our data do not support the existence of circulating PTH7-84 and oxidized PTH1-84.
Total, Bioavailable, and Free 25(OH)D Relationship with Indices of Bone Health in Elderly: A Randomized Controlled Trial
Sabeh, Malak El , Rahme, Maya , Halaby, Georges, Vanderschueren, Dirk , Bouillon, Roger , Fuleihan, Ghada El‐Hajj , El-Hajj Fuleihan, Ghada , Ghanem, Paola , Al‐Shaar, Laila , Baddoura, Rafic , Singh, Ravinder J.

The Journal of Clinical Endocrinology & Metabolism | December 6, 2020 | Volume: 106 | Issue: 2 | Pages: e990-e1001

10.1210/clinem/dgaa780 Get It

Abstract Context Questions regarding the superiority of free and bioavailable 25-hydroxyvitamin D [25(OH)D] in predicting health outcomes remain unresolved. Objective This study investigates the impact of vitamin D variables—total, bioavailable, or free 25(OH)D—on indices of bone and mineral metabolism, at baseline and in response to 2 vitamin D doses. Design Our objectives are implemented as exploratory analyses on data collected in a 1-year, double-blind, randomized controlled trial completed in July 2014. Setting Participants were recruited from 3 major hospitals in an ambulatory setting. Participants Participants were &gt;65 years of age, overweight, and had a baseline serum 25(OH)D between 10 and 30 ng/mL. A total of 221 participants completed the study. Intervention Subjects were randomized to receive calcium and oral vitamin D3 (600 IU/day or 3750 IU/day) supplementation. Results Participants who received the higher vitamin D dose had levels that were 1.3- to 1.4-fold higher than those taking the lower dose, for all variables (P value &lt; 0.001). Serum values of bioavailable and free 25(OH)D were associated with total 25(OH)D, with r values of 0.942 and 0.943, respectively (P value &lt; 0.001). Parathyroid hormone (PTH) was negatively associated with all vitamin D variables, with correlation coefficients ranging from −0.22 to −0.25, while calcium and bone turnover markers (carboxy-terminal collagen crosslinks and osteocalcin) did not. Only total 25(OH)D had a positive relationship with % change bone mineral density (BMD) at the femoral neck at 12 months, while only free and bioavailable 25(OH) had a positive relationship with % change total body BMD at 12 months. Conclusion Calculated free and bioavailable 25(OH)D do not appear to be superior to total 25(OH)D in predicting indices of bone health in an elderly population.