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"Sutton, S. Scott"
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Repurposing anti-inflammasome NRTIs for improving insulin sensitivity and reducing type 2 diabetes development
by
Gelfand, Bradley D.
,
Werner, Brian C.
,
Kerur, Nagaraj
in
631/250/256/2515
,
64/60
,
692/308/2778
2020
Innate immune signaling through the NLRP3 inflammasome is activated by multiple diabetes-related stressors, but whether targeting the inflammasome is beneficial for diabetes is still unclear. Nucleoside reverse-transcriptase inhibitors (NRTI), drugs approved to treat HIV-1 and hepatitis B infections, also block inflammasome activation. Here, we show, by analyzing five health insurance databases, that the adjusted risk of incident diabetes is 33% lower in patients with NRTI exposure among 128,861 patients with HIV-1 or hepatitis B (adjusted hazard ratio for NRTI exposure, 0.673; 95% confidence interval, 0.638 to 0.710; P < 0.0001; 95% prediction interval, 0.618 to 0.734). Meanwhile, an NRTI, lamivudine, improves insulin sensitivity and reduces inflammasome activation in diabetic and insulin resistance-induced human cells, as well as in mice fed with high-fat chow; mechanistically, inflammasome-activating short interspersed nuclear element (SINE) transcripts are elevated, whereas SINE-catabolizing DICER1 is reduced, in diabetic cells and mice. These data suggest the possibility of repurposing an approved class of drugs for prevention of diabetes.
Inflammasome activation may contribute to type 2 diabetes, but whether targeting inflammasome is beneficial is unclear. Here the authors show that repurposing nucleoside reverse transcriptase inhibitors for inhibiting inflammasome activation is associated with reduced diabetes development in people and improves insulin sensitivity in experimental settings.
Journal Article
Identification of fluoxetine as a direct NLRP3 inhibitor to treat atrophic macular degeneration
by
Gelfand, Bradley D.
,
Stains, Cliff I.
,
Taylor, Ethan W.
in
Age related diseases
,
Alu Elements - genetics
,
Animals
2021
The atrophic form of age-related macular degeneration (dry AMD) affects nearly 200 million people worldwide. There is no Food and Drug Administration (FDA)-approved therapy for this disease, which is the leading cause of irreversible blindness among people over 50 y of age. Vision loss in dry AMD results from degeneration of the retinal pigmented epithelium (RPE). RPE cell death is driven in part by accumulation of Alu RNAs, which are noncoding transcripts of a human retrotransposon. Alu RNA induces RPE degeneration by activating the NLRP3-ASC inflammasome. We report that fluoxetine, an FDA-approved drug for treating clinical depression, binds NLRP3 in silico, in vitro, and in vivo and inhibits activation of the NLRP3-ASC inflammasome and inflammatory cytokine release in RPE cells and macrophages, two critical cell types in dry AMD. We also demonstrate that fluoxetine, unlike several other antidepressant drugs, reduces Alu RNA–induced RPE degeneration in mice. Finally, by analyzing two health insurance databases comprising more than 100 million Americans, we report a reduced hazard of developing dry AMD among patients with depression who were treated with fluoxetine. Collectively, these studies identify fluoxetine as a potential drug-repurposing candidate for dry AMD.
Journal Article
Cytoplasmic synthesis of endogenous Alu complementary DNA via reverse transcription and implications in age-related macular degeneration
2021
Alu retroelements propagate via retrotransposition by hijacking long interspersed nuclear element-1 (L1) reverse transcriptase (RT) and endonuclease activities. Reverse transcription of Alu RNA into complementary DNA (cDNA) is presumed to occur exclusively in the nucleus at the genomic integration site. Whether Alu cDNA is synthesized independently of genomic integration is unknown. Alu RNA promotes retinal pigmented epithelium (RPE) death in geographic atrophy, an untreatable type of age-related macular degeneration. We report that Alu RNA-induced RPE degeneration is mediated via cytoplasmic L1–reverse-transcribed Alu cDNA independently of retrotransposition. Alu RNA did not induce cDNA production or RPE degeneration in L1-inhibited animals or human cells. Alu reverse transcription can be initiated in the cytoplasm via self-priming of Alu RNA. In four health insurance databases, use of nucleoside RT inhibitors was associated with reduced risk of developing atrophic macular degeneration (pooled adjusted hazard ratio, 0.616; 95% confidence interval, 0.493–0.770), thus identifying inhibitors of this Alu replication cycle shunt as potential therapies for a major cause of blindness.
Journal Article
Serum Bilirubin Levels and Risk of Venous Thromboembolism among Influenza Patients: A Cohort Study
by
Cummings, Tammy
,
Sutton, S. Scott
,
Hardin, James W.
in
Aged
,
Bilirubin - blood
,
Cohort analysis
2024
Objective
This study aimed to investigate the associations between total serum bilirubin levels and the incidence of venous thromboembolism (VTE) among patients with influenza infection.
Methods
A retrospective cohort study was conducted among outpatients with laboratory-confirmed influenza using data from the Veterans Affairs Informatics and Computing Infrastructure (VINCI). Propensity score weighting was applied to balance study groups across baseline covariates. Cox proportional hazards models assessed VTE risk by total bilirubin levels, adjusting for important covariates including age, sex, race, comorbidity index, BMI, and smoking status.
Results
A total of 487 patients with total bilirubin levels <0.3 mg/dL, 8608 patients with levels between 0.3–1 mg/dL, and 1148 patients with levels >1 mg/dL were included. Patients with bilirubin <0.3 mg/dL exhibited a 6-fold higher risk of VTE compared to those with levels 0.3–1 mg/dL within 30 days of infection (HR = 6.2, 95% CI = 1.46–26.42). Elevated risks were noted through 90 days post infection (HR = 4.71, 95% CI = (1.42–15.67))
Conclusions
Serum bilirubin levels, particularly below 0.3 mg/dL, were significantly associated with an increased risk of VTE among individuals with influenza. These findings suggest that lower bilirubin levels may contribute to heightened inflammatory responses and subsequent thromboembolic events in patients with influenza. The underlying mechanisms and potential therapeutic implications for VTE prevention among patients with acute respiratory infection warrants further consideration.
Journal Article
Association between Fluoxetine Use and Overall Survival among Patients with Cancer Treated with PD-1/L1 Immunotherapy
by
Ambati, Jayakrishna
,
Pereira, Felipe
,
Hardin, James W.
in
Antidepressants
,
Apoptosis
,
Cancer patients
2023
Checkpoint inhibitors can be a highly effective antitumor therapy but only to a subset of patients, presumably due to immunotherapy resistance. Fluoxetine was recently revealed to inhibit the NLRP3 inflammasome, and NLRP3 inhibition could serve as a target for immunotherapy resistance. Therefore, we evaluated the overall survival (OS) in patients with cancer receiving checkpoint inhibitors combined with fluoxetine. A cohort study was conducted among patients diagnosed with lung, throat (pharynx or larynx), skin, or kidney/urinary cancer treated with checkpoint inhibitor therapy. Utilizing the Veterans Affairs Informatics and Computing Infrastructure, patients were retrospectively evaluated during the period from October 2015 to June 2021. The primary outcome was overall survival (OS). Patients were followed until death or the end of the study period. There were 2316 patients evaluated, including 34 patients who were exposed to checkpoint inhibitors and fluoxetine. Propensity score weighted Cox proportional hazards demonstrated a better OS in fluoxetine-exposed patients than unexposed (HR: 0.59, 95% CI 0.371–0.936). This cohort study among cancer patients treated with checkpoint inhibitor therapy showed a significant improvement in the OS when fluoxetine was used. Because of this study’s potential for selection bias, randomized trials are needed to assess the efficacy of the association of fluoxetine or another anti-NLRP3 drug to checkpoint inhibitor therapy.
Journal Article
The Association Between Phosphodiesterase-5 Inhibitors and Colorectal Cancer in a National Cohort of Patients
by
Sutton, S. Scott
,
Hardin, James W.
,
Cummings, Tammy H.
in
Aged
,
Clinical outcomes
,
Colorectal cancer
2020
To examine the association between phosphodiesterase-5 (PDE-5) inhibitor use and incidence of colorectal cancer among patients with erectile dysfunction treated in the Veterans Affairs (VA) Healthcare System.
A retrospective cohort study using the Veterans Affairs Informatics and Computing Infrastructure was conducted, with data spanning January 2001-December 2016. Patients were followed up from index until (i) the first diagnosis of colorectal cancer, (ii) death, or (iii) the end of study period. Statistical analyses evaluated demographics and baseline characteristics between cohorts (PDE-5 exposed or not) and the effect of additional dosages of each specific PDE-5 inhibitor using adjusted multivariate Cox proportional hazards models.
A total of 221,538 patients met the study inclusion criteria, 192,691 patients in the PDE-5 cohort and 29,227 patients in the never use PDE-5 cohort. The multivariate Cox proportional hazards model results revealed that the those who had any exposure to a PDE-5 inhibitor have an 18% lower hazard of colorectal cancer (adjusted hazard ratio [HR] = 0.816, 95% confidence interval [CI] = 0.754-0.882). For each additional 100-mg dosage of sildenafil and 10-mg dosage of tadalafil, the hazard of colorectal cancer is reduced by 2.4% (adjusted HR = 0.976, 95% CI = 0.973-0.979) and 1.7% (adjusted HR = 0.983, 95% CI = 0.972-0.996), respectively.
PDE-5 inhibitor usage in patients with erectile dysfunction is associated with a lower hazard of colorectal cancer compared with patients not exposed to PDE-5 inhibitors.
Journal Article
Anti‐HIV drugs reduce risk of prediabetes and progression to type 2 diabetes in HIV‐infected patients
by
Nguyen, Joseph
,
Ambati, Jayakrishna
,
Pereira, Felipe
in
Cardiovascular disease
,
Comorbidity
,
Diabetes
2023
The aim of this study was to investigate whether the use of nucleoside reverse transcriptase inhibitors (NRTIs) impacts the incidence of prediabetes or type 2 diabetes mellitus (T2DM) or the progression from prediabetes to T2DM in people living with HIV (PLWH). We conducted a retrospective cohort study using the US Veterans Health Administration database among adult patients with an HIV diagnosis from the year 2000 until 2021 to determine the incidence of prediabetes and further progression to T2DM among NRTI exposed and unexposed patients. A multistate model was used to evaluate progression from normoglycemia to prediabetes and then to T2DM, and covariate adjustment with the Cox proportional hazards model was used to estimate the hazard ratios (HRs). Among 32,240 veterans diagnosed with HIV, prediabetes and T2DM were observed among 20.2% and 20.7% of patients, respectively. Among those diagnosed with prediabetes, 31.8% progressed to T2DM. Patients exposed to NRTIs at any time (86.6%), had a reduced risk of prediabetes [HR: 0.50 (95% confidence interval, CI: 0.47–0.53)] and among prediabetics, a lower risk of progression to T2DM [HR: 0.73 (95% CI: 0.63–0.85)] when compared to patients who never used NRTIs. In summary, NRTIs may reduce the risk of developing prediabetes and the progression from prediabetes to T2DM in PLWH. In this 20‐year retrospective analysis of a nationwide database, people living with HIV who were exposed to nucleoside reverse transcriptase inhibitors (NRTIs) had a decreased risk of developing prediabetes or progressing from prediabetes to type 2 diabetes mellitus.
Journal Article
Odds of Achieving Target Serum Uric Acid Levels Among Gout Patients: The Role of Rurality in Outcomes and Treatment Adherence
2023
Objective:
The goal of this paper was to analyze patient outcomes related to gout treatment including, serum uric acid (sUA) measures and treatment adherence across patients in metropolitan, micropolitan or rural counties.
Methods:
We conducted a drug-disease cohort study among patients with gout initiating urate lowering therapy. The proportion of patients with sUA < 6 mg/dL at 1 year of follow-up is compared over the cohort groups using a chi-square test and adjusted logistic regression. Adherence to urate lowering therapy was calculated using the proportion of days covered (PDC). A T-test was used to compare the average PDC and an adjusted logistic regression model was used to estimate the odds of a PDC greater than 80%.
Results:
A total of 9922 patients were included in the study. Most patients were in a metropolitan (77.4%) area, followed by micropolitan (11.8%) and finally, (10.8%) in a rural area. We found no statistically significant difference among the proportion of patients achieving target sUA of <6 mg/dL, 37.17% among metropolitan patients, 38.9% among micropolitan patients, and 37.7% for those in a rural area, P-value = .502. The proportion of patients achieving 80% treatment adherence was 49.92% in the metropolitan, 51.78% in the micropolitan, and 55.05% in the rural areas, P-value = .005. Adjusted regression models showed no statistically significant difference in proportions achieving target sUA levels or 80% adherence.
Conclusions:
Urban patients treated for gout did not have better gout outcomes compared to rural patients. Future research should consider provider-based interventions to improve outcomes.
Journal Article
Patients with Obesity and a History of Metformin Treatment Have Lower Influenza Mortality: A Retrospective Cohort Study
by
Sutton, S. Scott
,
Hardin, James W.
,
Cummings, Tammy H.
in
algorithms
,
Cohort analysis
,
cohort studies
2022
Background: Obesity is a risk factor for the development of influenza by leading to a chronic inflammatory state and T-cell dysfunction. Based upon preclinical research, metformin has influenza activity by restoring T-cell function and improving the immune response. Objective: We aimed to evaluate the potential drug repurposing of metformin for the management of influenza among patients with obesity utilizing national claims data in an electronic health record database. Methods: The VA Informatics and Computing Infrastructure (VINCI) was utilized to obtain individual-level information on demographics, administrative claims, and pharmacy dispensation. A cohort was created among individuals with laboratory confirmed diagnosis of influenza with a diagnosis of fever, cough, influenza, or acute upper respiratory infection in an outpatient setting. The study outcome was death after diagnosis of influenza. Cohorts were formed using diabetes status and metformin exposure prior to a positive influenza diagnosis. Hazard ratios for mortality were estimated using a cox proportional hazards model adjusting for baseline covariates and a sub-analysis was conducted utilizing propensity score matching. A greedy nearest neighbor algorithm was utilized to match 1 to 1 non-metformin diabetic controls and non-diabetic controls to diabetic patients receiving metformin. Results: A total of 3551 patients met the inclusion criteria and were evaluated in our study. The cohorts consisted of 1461 patients in the non-diabetic cohort, 1597 patients in the diabetic / metformin cohort, and 493 patients in the diabetic no metformin cohort. Compared to non-diabetic patients, diabetic patients with metformin had a lower rate of death (aHR 0.78, 95% CI 0.609–0.999). There was not a statistical difference between the non-diabetic patients and the diabetic patients without metformin (aHR 1.046, 95% CI 0.781–1.400). The propensity score matched cohorts revealed consistent results with the primary analysis. Conclusion: Our results demonstrated patients with obesity and a history of metformin treatment have lower influenza mortality.
Journal Article
Melatonin as an Antimicrobial Adjuvant and Anti-Inflammatory for the Management of Recurrent Clostridioides difficile Infection
2022
Background: Clostridioides difficile (C. difficile) infection (CDI) is strongly associated with inflammation and has the potential to cause recurrent infections. Pre-clinical data suggest that melatonin has beneficial effects in the gastrointestinal tract due to its anti-inflammatory and antibacterial properties. This analysis examines the association between melatonin and the risk of recurrent CDI. Methods: A retrospective cohort study was conducted among patients with an inpatient diagnosis of CDI along with a positive C. difficile polymerase chain reaction (PCR) or enzyme immunoassay (EIA) test result. Patients were followed until the first study end point (death) or the first instance of recurrent infection. Propensity-score weighting was utilized accounting for confounding factors and weighted Cox models were estimated. Results: A total of 24,782 patients met the inclusion criteria, consisting of 3457 patients exposed to melatonin and 21,325 patients with no melatonin exposure. The results demonstrate that those exposed to melatonin were associated with a 21.6% lower risk of recurrent CDI compared to patients without melatonin exposure (HR = 0.784; 95% CI = 0.674–0.912). Conclusion: Our results demonstrate a decreased rate of recurrent CDI in patients exposed to melatonin. Further research on melatonin as an antimicrobial adjuvant and anti-inflammatory is warranted for the management of recurrent CDI.
Journal Article