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Role of the Gut in the Temporal Changes of β-Cell Function After Gastric Bypass in Individuals With and Without Diabetes Remission

Prasad, Malini; Mark, Victoria; Ligon, Chanel; Dutia, Roxanne; Nair, Nandini; Shah, Ankit; Laferrère, Blandine
OBJECTIVE:The role of the gut in diabetes remission after Roux-en-Y gastric bypass (RYGB) is incompletely understood. We assessed the temporal change in insulin secretory capacity after RYGB, using oral and intravenous (IV) glucose, in individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS/METHODS:Longitudinal, prospective measures of β-cell function were assessed after oral glucose intake and graded glucose infusion in individuals with severe obesity and diabetes studied at 0, 3 (n = 29), 12 (n = 24), and 24 (n = 20) months after RYGB. Data were collected between 2015 and 2019 in an academic clinical research center. RESULTS:= not significant). The improvement in β-cell function after IV glucose administration was not apparent until 12 months, significant only in those in full remission, and only ∼33% of that observed after oral glucose intake. Preintervention β-cell function and its change after surgery predicted remission; weight loss and insulin sensitivity did not. CONCLUSION/CONCLUSIONS:Our data show the time course of changes in β-cell function after RYGB. The improvement in β-cell function after RYGB, but not changes in weight loss or insulin sensitivity, drives diabetes remission.
PMID: 34857533
ISSN: 1935-5548
CID: 5081282

Temporal Eating Patterns and Eating Windows among Adults with Overweight or Obesity

Popp, Collin J; Curran, Margaret; Wang, Chan; Prasad, Malini; Fine, Keenan; Gee, Allen; Nair, Nandini; Perdomo, Katherine; Chen, Shirley; Hu, Lu; St-Jules, David E; Manoogian, Emily N C; Panda, Satchidananda; Sevick, Mary Ann; Laferrère, Blandine
We aim to describe temporal eating patterns in a population of adults with overweight or obesity. In this cross-sectional analysis, data were combined from two separate pilot studies during which participants entered the timing of all eating occasions (>0 kcals) for 10-14 days. Data were aggregated to determine total eating occasions, local time of the first and last eating occasions, eating window, eating midpoint, and within-person variability of eating patterns. Eating patterns were compared between sexes, as well as between weekday and weekends. Participants (n = 85) had a median age of 56 ± 19 years, were mostly female (>70%), white (56.5%), and had a BMI of 31.8 ± 8.0 kg/m2. The median eating window was 14 h 04 min [12 h 57 min-15 h 21 min], which was significantly shorter on the weekend compared to weekdays (p < 0.0001). Only 13.1% of participants had an eating window <12 h/d. Additionally, there was greater irregularity with the first eating occasion during the week when compared to the weekend (p = 0.0002). In conclusion, adults with overweight or obesity have prolonged eating windows (>14 h/d). Future trials should examine the contribution of a prolonged eating window on adiposity independent of energy intake.
PMID: 34960035
ISSN: 2072-6643
CID: 5108062

Associations of Body Mass Index and Waist Circumference in Young Adulthood with Later Life Incident Diabetes

Nair, Nandini; Vittinghoff, Eric; Pletcher, Mark J; Oelsner, Elizabeth C; Allen, Norrina B; Ndumele, Chiadi E; West, Nancy A; Strotmeyer, Elsa S; Mukamal, Kenneth J; Siscovick, David S; Biggs, Mary L; Laferrère, Blandine; Moran, Andrew E; Zhang, Yiyi
CONTEXT:The independent contribution of young adult exposure to overweight and obesity to later-life incident diabetes is not well studied. OBJECTIVE:To assess the associations of exposures to elevated body mass index (BMI) and waist circumference (WC) in young adulthood (ages 18-39 years) with incident diabetes later in life (≥40 years). DESIGN:Pooled data from 6 US prospective cohorts (Atherosclerosis Risk in Communities Study, Cardiovascular Risk Development in Young Adults Study, Cardiovascular Health Study, (4) Framingham Heart Study Offspring Cohort, (5) Health, Aging and Body Composition Study, and (6) Multi-Ethnic Study of Atherosclerosis. SETTING:Population-based cohort studies. PARTICIPANTS:30 780 participants (56.1% female, 69.8% non-Hispanic white) without a diagnosis of diabetes by age 40. INTERVENTIONS:We imputed BMI and WC trajectories from age 18 for every participant and estimated time-weighted average exposures to BMI or WC during young adulthood and later life. MAIN OUTCOME MEASURE(S):Incident diabetes defined as fasting glucose ≥126 mg/dL, nonfasting glucose ≥200 mg/dL, or use of diabetes medications. RESULTS:During a 9-year median follow-up, 4323 participants developed incident diabetes. Young adult BMI and WC were associated with later-life incident diabetes after controlling for later-life exposures [hazard ratios (HR) 1.99 for BMI ≥ 30 kg/m2 and 2.13 for WC > 88cm (women)/>102cm (men) compared to normal ranges]. Young adult homeostatic model of insulin resistance mediated 49% and 44% of the association between BMI and WC with later-life incident diabetes. High-density lipoproteins and triglycerides mediated a smaller proportion of these associations. CONCLUSIONS:Elevated BMI and WC during young adulthood were independently associated with later-life incident diabetes. Insulin resistance may be a key mediator.
PMID: 34302728
ISSN: 1945-7197
CID: 5081242

A Smartphone Intervention to Promote Time Restricted Eating Reduces Body Weight and Blood Pressure in Adults with Overweight and Obesity: A Pilot Study

Prasad, Malini; Fine, Keenan; Gee, Allen; Nair, Nandini; Popp, Collin J; Cheng, Bin; Manoogian, Emily N C; Panda, Satchidananda; Laferrère, Blandine
The goal of this study was to test the feasibility of time restricted eating (TRE) in adults with overweight and obesity. Participants (n = 50) logged all eating occasions (>0 kcal) for a 2-week run-in period using a smartphone application. Participants with eating duration ≥14 h enrolled in an open label, non-randomized, prospective 90-day TRE intervention, with a self-selected reduced eating window of 10 h. No dietary counseling was provided. Changes in anthropometrics, eating patterns and adherence after TRE were analyzed using t-tests or Wilcoxon Rank-Sum Test. The mean duration of the baseline eating window was 14 h 32 m ± 2 h 36 m (n = 50) with 56% of participants with duration ≥14 h. TRE participants (n = 16) successfully decreased their eating window from 16 h 04 m ± 1 h 24 m to 11 h 54 m ± 2 h 06 m (p < 0.001), and reduced the number of daily eating occasions by half (p < 0.001). Adherence to logging and to the reduced eating window was 64% ± 22% and 47% ± 19%, respectively. TRE resulted in decreases in body weight (-2.1 ± 3.0 kg, p = 0.017), waist circumference (-2.2 ± 4.6 cm, p = 0.002) and systolic blood pressure (-12 ± 11 mmHg, p = 0.002). This study demonstrates the feasibility and efficacy of TRE administered via a smartphone, in adults with overweight and obesity.
PMID: 34201442
ISSN: 2072-6643
CID: 5081232


Bilezikian, John P; Bikle, Daniel; Hewison, Martin; Lazaretti-Castro, Marise; Formenti, Anna Maria; Gupta, Aakriti; Madhavan, Mahesh V; Nair, Nandini; Babalyan, Varta; Hutchings, Nicholas; Napoli, Nicola; Accili, Domenico; Binkley, Neil; Landry, Donald W; Giustina, Andrea
The SARS-CoV-2 virus responsible for the COVID-19 pandemic has generated an explosion of interest both in the mechanisms of infection leading to dissemination and expression of this disease, and in potential risk factors that may have a mechanistic basis for disease propagation or control. Vitamin D has emerged as a factor that may be involved in these two areas. The focus of this article is to apply our current understanding of vitamin D as a facilitator of immunocompetence both with regard to innate and adaptive immunity and to consider how this may relate to COVID-19 disease. There are also intriguing potential links to vitamin D as a factor in the cytokine storm that portends some of the most serious consequences of SARS-CoV-2 infection, such as the acute respiratory distress syndrome. Moreover, cardiac and coagulopathic features of COVID-19 disease deserve attention as they may also be related to vitamin D. Finally, we review the current clinical data associating vitamin D with SARS-CoV-2 infection, a putative clinical link that at this time must still be considered hypothetical.
PMID: 32755992
ISSN: 1479-683x
CID: 4640452

Effect of Teriparatide on Bone Remodeling and Density in Premenopausal Idiopathic Osteoporosis: A Phase II Trial

Cohen, Adi; Shiau, Stephanie; Nair, Nandini; Recker, Robert R; Lappe, Joan M; Dempster, David W; Nickolas, Thomas L; Zhou, Hua; Agarwal, Sanchita; Kamanda-Kosseh, Mafo; Bucovsky, Mariana; Williams, John M; McMahon, Donald J; Stubby, Julie; Shane, Elizabeth
CONTEXT:Premenopausal women with idiopathic osteoporosis (IOP) have abnormal skeletal microarchitecture and variable tissue-level bone formation rate (BFR). OBJECTIVES:Compare 6 months (M) of teriparatide versus placebo on areal bone mineral density (aBMD) by dual-energy x-ray absorptiometry (DXA), bone turnover markers (BTMs) and BFR at 3M by quadruple-labeled transiliac biopsy. Characterize 12M and 24M effects of teriparatide on aBMD and whether BTMs and BFR predict response. DESIGN:6M phase 2 randomized controlled trial (RCT) followed by open extension. SETTING:Tertiary referral centers. PATIENTS:Premenopausal women with IOP. INTERVENTIONS:A total of 41 women were randomized to either teriparatide 20 mcg (n = 28) or placebo (n = 13). After 6M, those on placebo switched to teriparatide for 24M; those on teriparatide continued for 18M. MAIN OUTCOME MEASURES:6M RCT: Between-group differences in lumbar spine (LS) aBMD (percent change from baseline), 3M BFR, and hypercalcemia. Open-label extension: Within-group change in LS aBMD over 12M and 24M. Secondary outcomes included aBMD change at other sites and relationship between BTMs, BFR, and changes in aBMD. FINDINGS:Over 6M, LS aBMD increased by 5.5% (95% CI: 3.83, 7.19) in teriparatide and 1.5% (95% CI: -0.73, 3.83) in placebo (P = 0.007). There were increases in 3M BTMs, and BFR (cancellous and endocortical BFR: between-groups P = 0.004). Over 24M, teriparatide increased LS aBMD by 13.2% (95% CI: 10.3, 16.2), total hip by 5.2% (95% CI: 3.7, 6.7) and femoral neck by 5.0% (95% CI: 3.2, 6.7; all P ≤ 0.001). Serum N-terminal propeptides of procollagen type 1 (P1NP) and 3M endocortical BFR were moderately associated with LS aBMD response. Teriparatide was well-tolerated. CONCLUSIONS:Teriparatide increased BFR and formation markers and was associated with marked aBMD improvements in most premenopausal women (82%) with IOP.
PMID: 32876328
ISSN: 1945-7197
CID: 5081142

Extrapulmonary manifestations of COVID-19

Gupta, Aakriti; Madhavan, Mahesh V; Sehgal, Kartik; Nair, Nandini; Mahajan, Shiwani; Sehrawat, Tejasav S; Bikdeli, Behnood; Ahluwalia, Neha; Ausiello, John C; Wan, Elaine Y; Freedberg, Daniel E; Kirtane, Ajay J; Parikh, Sahil A; Maurer, Mathew S; Nordvig, Anna S; Accili, Domenico; Bathon, Joan M; Mohan, Sumit; Bauer, Kenneth A; Leon, Martin B; Krumholz, Harlan M; Uriel, Nir; Mehra, Mandeep R; Elkind, Mitchell S V; Stone, Gregg W; Schwartz, Allan; Ho, David D; Bilezikian, John P; Landry, Donald W
Although COVID-19 is most well known for causing substantial respiratory pathology, it can also result in several extrapulmonary manifestations. These conditions include thrombotic complications, myocardial dysfunction and arrhythmia, acute coronary syndromes, acute kidney injury, gastrointestinal symptoms, hepatocellular injury, hyperglycemia and ketosis, neurologic illnesses, ocular symptoms, and dermatologic complications. Given that ACE2, the entry receptor for the causative coronavirus SARS-CoV-2, is expressed in multiple extrapulmonary tissues, direct viral tissue damage is a plausible mechanism of injury. In addition, endothelial damage and thromboinflammation, dysregulation of immune responses, and maladaptation of ACE2-related pathways might all contribute to these extrapulmonary manifestations of COVID-19. Here we review the extrapulmonary organ-specific pathophysiology, presentations and management considerations for patients with COVID-19 to aid clinicians and scientists in recognizing and monitoring the spectrum of manifestations, and in developing research priorities and therapeutic strategies for all organ systems involved.
PMID: 32651579
ISSN: 1546-170x
CID: 5081112

Peripheral retinal ischaemia, as evaluated by ultra-widefield fluorescein angiography, is associated with diabetic macular oedema

Wessel, Matthew M; Nair, Nandini; Aaker, Grant D; Ehrlich, Joshua R; D'Amico, Donald J; Kiss, Szilárd
PURPOSE/OBJECTIVE:To determine the relationship between retinal ischaemia and the presence of macular oedema (DMO) in patients with diabetic retinopathy (DR) using ultra-widefield fluorescein angiography (UWFA) imaging. METHODS:A retrospective review of 122 eyes of 70 treatment-naïve diabetic patients who underwent diagnostic UWFA using the Optos 200Tx imaging system. Two independent, masked graders quantified the area of retinal ischaemia. Based on clinical examination and optical coherence tomography (OCT), each patient was given a binary classification as either having DMO or no DMO. McNemar's test (with Yates' correction as indicated) and a two-sample test of proportions were used to determine the relationship between DMO and ischaemia for binary and proportional data, respectively. Linear and logistic models were constructed using generalised estimating equations to test relationships between independent variables, covariates and outcomes while controlling for inter-eye correlation, age, gender, haemoglobin A1c, mean arterial pressure and dependence on insulin. RESULTS:Seventy-six eyes (62%) exhibited areas of retinal ischaemia. There was a significant direct correlation between DMO and peripheral retinal ischaemia as seen on UWFA (p<0.001). In addition, patients with retinal ischaemia had 3.75 times increased odds of having DMO compared with those without retinal ischaemia (CI 1.26 to 11.13, p<0.02). CONCLUSION/CONCLUSIONS:Retinal ischaemia is significantly correlated with DMO in treatment-naïve patients with DR. UWFA is a useful tool for detecting peripheral retinal ischaemia, which may have direct implications in the diagnosis, follow-up and treatment such as targeted peripheral photocoagulation.
PMID: 22423055
ISSN: 1468-2079
CID: 4493902

Acute and chronic responses to the convulsant pilocarpine in DBA/2J and A/J mice

Winawer, M R; Makarenko, N; McCloskey, D P; Hintz, T M; Nair, N; Palmer, A A; Scharfman, H E
Characterizing the responses of different mouse strains to experimentally-induced seizures can provide clues to the genes that are responsible for seizure susceptibility, and factors that contribute to epilepsy. This approach is optimal when sequenced mouse strains are available. Therefore, we compared two sequenced strains, DBA/2J (DBA) and A/J. These strains were compared using the chemoconvulsant pilocarpine, because pilocarpine induces status epilepticus, a state of severe, prolonged seizures. In addition, pilocarpine-induced status is followed by changes in the brain that are associated with the pathophysiology of temporal lobe epilepsy (TLE). Therefore, pilocarpine can be used to address susceptibility to severe seizures, as well as genes that could be relevant to TLE. A/J mice had a higher incidence of status, but a longer latency to status than DBA mice. DBA mice exhibited more hippocampal pyramidal cell damage. DBA mice developed more ectopic granule cells in the hilus, a result of aberrant migration of granule cells born after status. DBA mice experienced sudden death in the weeks following status, while A/J mice exhibited the most sudden death in the initial hour after pilocarpine administration. The results support previous studies of strain differences based on responses to convulsants. They suggest caution in studies of seizure susceptibility that are based only on incidence or latency. In addition, the results provide new insight into the strain-specific characteristics of DBA and A/J mice. A/J mice provide a potential resource to examine the progression to status. The DBA mouse may be valuable to clarify genes regulating other seizure-associated phenomena, such as seizure-induced neurogenesis and sudden death
PMID: 17904758
ISSN: 0306-4522
CID: 76102