Bradley Howlett

Mr. Bradley Howlett


Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2020 in Journal of Strength & Conditioning Research
Verified
Journal Article
Closed access
JBJames R. Bagley
James R. Bagley
KBKyle J. Burghardt
Kyle J. Burghardt
RMRyan McManus
Ryan McManus
BHBradley Howlett
Bradley Howlett
PCPablo B. Costa
Pablo B. Costa
AGAndrew Galpin
Andrew Galpin
Bagley, JR, Burghardt, KJ, McManus, R, Howlett, B, Costa, PB, Coburn, JW, Arevalo, JA, Malek, MH, and Galpin, AJ. Epigenetic responses to acute resistance exercise in trained vs. sedentary men. J Strength Cond Res 34(6): 1574–1580, 2020—Acute resistance exercise (RE) alters DNA methylation, an epigenetic process that influences gene expression and regulates skeletal muscle adaptation. This aspect of cellular remodeling is poorly understood, especially in resistance-trained (RT) individuals. The study purpose was to examine DNA methylation in response to acute RE in RT and sedentary (SED) young men, specifically targeting genes responsible for metabolic, inflammatory, and hypertrophic muscle adaptations. Vastus lateralis biopsies were performed before (baseline), 30 minutes after, and 4 hours after an acute RE bout (3 × 10 repetitions at 70% 1 repetition maximum [1RM] leg press and leg extension) in 11 RT (mean ± SEM: age = 26.1 ± 1.0 years; body mass = 84.3 ± 0.2 kg; leg press 1RM = 412.6 ± 25.9 kg) and 8 SED (age = 22.9 ± 1.1 years; body mass = 75.6 ± 0.3 kg; leg press 1RM = 164.8 ± 22.5 kg) men. DNA methylation was analyzed through methylation sensitive high-resolution melting using real-time polymerase chain reaction. Separate 2 (group) × 3 (time) repeated-measures analyses of variance and analyses of covariance were performed to examine changes in DNA methylation for each target gene. Results showed that acute RE (a) hypomethylated LINE-1 (measure of global methylation) in RT but not SED, (b) hypermethylated metabolic genes (GPAM and SREBF2) in RT, while lowering SREBF2 methylation in SED, and (c) did not affect methylation of genes associated with inflammation (IL-6 and TNF-α) or hypertrophy (mTOR and AKT1). However, basal IL-6 and TNF-α were lower in SED compared with RT. These findings indicate the same RE stimulus can illicit different epigenetic responses in RT vs. SED men and provides a molecular mechanism underpinning the need for differential training stimuli based on subject training backgrounds.

1 July 2020 in Research in Social and Administrative Pharmacy
Verified
Journal Article
Closed access
KBKyle Burghardt
Kyle Burghardt
BHBradley Howlett
Bradley Howlett
SFStephanie M. Fern
Stephanie M. Fern
PBPaul R. Burghardt
Paul R. Burghardt

1 April 2020 in Publications
Verified
Journal Article
Open access
PDF file
KBKyle Burghardt
Kyle Burghardt
BHBradley Howlett
Bradley Howlett
AKAudrey S. Khoury
Audrey S. Khoury
SFStephanie M. Fern
Stephanie M. Fern
PBPaul Burghardt
Paul Burghardt
Scholarly productivity is a critical component of pharmacy faculty effort and is used for promotion and tenure decisions. Several databases are available to measure scholarly productivity; however, comparisons amongst these databases are lacking for pharmacy faculty. The objective of this work was to compare scholarly metrics from three commonly utilized databases and a social networking site focused on data from research-intensive colleges of pharmacy and to identify factors associated with database differences. Scholarly metrics were obtained from Scopus, Web of Science, Google Scholar, and ResearchGate for faculty from research-intensive (Carnegie Rated R1, R2, or special focus) United States pharmacy schools with at least two million USD in funding from the National Institutes of Health. Metrics were compared and correlations were performed. Regression analyses were utilized to identify factors associated with database differences. Significant differences in scholarly metric values were observed between databases despite the high correlations, suggestive of systematic variation in database reporting. Time since first publication was the most common factor that was associated with database differences. Google Scholar tended to have higher metrics than all other databases, while Web of Science had lower metrics relative to other databases. Differences in reported metrics between databases are apparent, which may be attributable to the time since first publication and database coverage of pharmacy-specific journals. These differences should be considered by faculty, reviewers, and administrative staff when evaluating scholarly performance.

1 December 2019 in European Neuropsychopharmacology
Verified
Journal Article
Closed access
KBKyle Burghardt
Kyle Burghardt
BHBradley Howlett
Bradley Howlett
ESElani Sanders
Elani Sanders
SDSabrina E. Dass
Sabrina E. Dass
ZMZaher Msallaty
Zaher Msallaty
ZYZhengping Yi
Zhengping Yi

10 May 2024 in Biomedicines
Verified
Journal Article
Open access
PDF file
KBKyle Burghardt
Kyle Burghardt
PBPaul Burghardt
Paul Burghardt
BHBradley Howlett
Bradley Howlett
SDSabrina E. Dass
Sabrina E. Dass
BZBrent Zahn
Brent Zahn
ZYZhengping Yi
Zhengping Yi
Antipsychotics are associated with severe metabolic side effects including insulin resistance; however, the mechanisms underlying this side effect are not fully understood. The skeletal muscle plays a critical role in insulin-stimulated glucose uptake, and changes in skeletal muscle DNA methylation by antipsychotics may play a role in the development of insulin resistance. A double-blind, placebo-controlled trial of olanzapine was performed in healthy volunteers. Twelve healthy volunteers were randomized to receive 10 mg/day of olanzapine for 7 days. Participants underwent skeletal muscle biopsies to analyze DNA methylation changes using a candidate gene approach for the insulin signaling pathway. Ninety-seven methylation sites were statistically significant (false discovery rate < 0.05 and beta difference between the groups of ≥10%). Fifty-five sites had increased methylation in the skeletal muscle of olanzapine-treated participants while 42 were decreased. The largest methylation change occurred at a site in the Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-Alpha (PPARGC1A) gene, which had 52% lower methylation in the olanzapine group. Antipsychotic treatment in healthy volunteers causes significant changes in skeletal muscle DNA methylation in the insulin signaling pathway. Future work will need to expand on these findings with expression analyses.

13 October 2018 in Metabolites
Verified
Journal Article
Open access
PDF file
KBKyle Burghardt
Kyle Burghardt
KWKristen Ward
Kristen Ward
ESElani J. Sanders
Elani J. Sanders
BHBradley Howlett
Bradley Howlett
BSBerhane Seyoum
Berhane Seyoum
ZYZhengping Yi
Zhengping Yi
Atypical antipsychotics (AAPs) are a class of medications associated with significant metabolic side effects, including insulin resistance. The aim of this study was to analyze the skeletal muscle lipidome of patients on AAPs, compared to mood stabilizers, to further understand the molecular changes underlying AAP treatment and side effects. Bipolar patients on AAPs or mood stabilizers underwent a fasting muscle biopsy and assessment of insulin sensitivity. A lipidomic analysis of total fatty acids (TFAs), phosphatidylcholines (PCs) and ceramides (CERs) was performed on the muscle biopsies, then lipid species were compared between treatment groups, and correlation analyses were performed with insulin sensitivity. TFAs and PCs were decreased and CERs were increased in the AAP group relative to those in the mood stabilizer group (FDR q-value <0.05). A larger number of TFAs and PCs were positively correlated with insulin sensitivity in the AAP group compared to those in the mood stabilizer group. In contrast, a larger number of CERs were negatively correlated with insulin sensitivity in the AAP group compared to that in the mood stabilizer group. The findings here suggest that AAPs are associated with changes in the lipid profiles of human skeletal muscle when compared to mood stabilizers and that these changes correlate with insulin sensitivity.