Citations

Epinephrine is a sympathomimetic which is derived from phenylalanine and tyrosine. The final step of epinephrine synthesis, the conversion from norepinephrine, relies on phenylethanolamine N‐methyltransferase (PNMT). The beta‐2 adrenergic receptor (ADRB2) binds to epinephrine and has several common functional polymorphisms including a Glycine (Gly) for Arginine (Arg) substitution at amino acid 16. We assessed the effect of the gene‐to‐gene interaction of these proteins on the ventricular response to exercise in healthy humans (n=69, age=29±6yrs, ht=174±10cm, wt=71±13kg). We found that within the 2*1 haplotype of the 5′FR, which has previously demonstrated greater epinephrine synthesis compared to 2*7 haplotype, the Arg16 genotype demonstrates lower stroke volume (SV) than the Gly16 genotype despite similar epinephrine levels and synthesis rates (Arg16= 75±5, Gly16=89±6ml/beat). Similarly, within the 2*7 haplotype of the 5′FR, which has demonstrated attenuated epinephrine synthesis compared to 2*1, the Arg16 genotype demonstrates a smaller SV than the Gly16 genotype (Arg16= 59±3, Gly16=78±6ml/beat). Additionally, the Arg16 and Gly16 subjects within the 2*1 haplotype of PNMT have greater stroke volume than their ADRB2 counterparts of the 2*7 haplotype of PNMT. These data demonstrate an interaction between the genes that encode PNMT and ADRB2 on the ventricular response to exercise.

Background: The mechanisms responsible for cardiac injury in the early stage of metabolic syndrome (MetS) remain unknown. Mitochondria are intimately associated with myofibrils, where the cytoskeleton functions as a linkage coordinator. We hypothesized that early MetS is characterized by cytoskeletal-mitochondrial disorganization, and that mitoprotection with mitochondria-targeted peptides (MTP) would preserve cytoskeletal-mitochondrial structure and attenuate myocardial injury in early swine MetS. Methods: Pigs were studied after 16wks of diet-induced MetS, MetS treated for the last 4wks with the MTP Elamipretide (0.1mg/kg SC q.d), and Lean controls (n=6 each). Cardiac function (multidetector CT) was assessed in-vivo, and mitochondrial structure (electron microscopy), the mitochondrial inner membrane phospholipid cardiolipin (mass spectrometry), cytoskeletal proteins, oxidative stress, and apoptosis ex-vivo. Results: MetS pigs developed hypertension and insulin resistance, yet cardiac function was preserved. MetS induced loss of desmin and tubulin that was paralleled by mitochondrial disorganization, decreased 18:2 cardiolipin, and increased oxidative stress and apoptosis. MTP slightly improved cardiolipin species profile, restored mitochondrial organization, and upregulated cytoskeletal proteins, attenuating apoptosis and oxidative stress. Conclusion: Early MetS leads to disorganization of the cardiomyocyte cytoskeletal- mitochondrial architecture and cardiac injury. MTP may provide a novel therapeutic potential for improving cardiac injury in early MetS, and potentially preventing future deterioration in cardiac function.

Frataxin is a conserved mitochondrial protein whose deficiency causes mitochondrial iron imbalance, energy deficit, and oxidative stress, leading to the progressive neurologic and cardiac disease Friedreich ataxia. We reported previously that the mature form of human frataxin is degraded to shorter products by an unknown protease, designated frataxin degrading peptidase (FDP). We hypothesized that FDP might represent a new mechanism to modulate mitochondrial iron balance via regulation of frataxin turnover. We have now purified FDP from different tissue sources. Interestingly, the enzyme corresponds to a known mitochondrial homodimeric oxidoreductase involved in energy metabolism and antioxidant defense. The presence of proteolytic activity has been confirmed with a recombinant form of the oxidoreductase produced in E. coli . The 3D structure of the enzyme suggests the presence of a Ser‐His‐Glu catalytic triad at the homodimer interface. Indeed, the proteolytic activity is stimulated by point mutations or other conditions that destabilize the homodimer, and is inactivated by certain serine protease inhibitors. Combining oxidoreductase and proteolytic functions in the same protein may be a mechanism to integrate changes in energy metabolism and redox status with mitochondrial iron balance. [Supported by the Muscular Dystrophy Association and a pre‐doctoral fellowship from the American Heart Association (0415379Z)].

TPS3161 Background: The p53 pathway has been implicated in antitumor immunity, including antigen presentation and T-cell proliferation. Loss of p53 function can increase resistance to immunotherapy across many tumor types. Eprenetapopt (eprenet) is a small molecule that stabilizes the folded structure of p53, resulting in activation of mutant p53 and stabilization of wild-type (WT) p53. It also targets the cellular redox homeostasis, resulting in induction of apoptosis in tumor cells. In vivo, mice carrying supernumerary copies of the TP53 gene harbor a pro-inflammatory tumor microenvironment, an effect recapitulated in TP53 normal-copy mice treated with eprenetapopt. Combining eprenetapopt and anti-PD1 or anti-CTLA4 therapy resulted in enhanced tumor growth inhibition and improved survival in TP53 WT mice inoculated with B16 melanoma and MC38 colon adenocarcinoma cells . Based on these results, we hypothesized that eprenet-induced p53 stabilization may augment response to immunotherapy. To test this hypothesis, we are conducting a phase 1b/2 study of eprenet in combination with pembrolizumab (eprenet+pembro) in pts with solid tumors. Methods: The primary objectives are to determine the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) and to assess the safety and tolerability of eprenet+pembro in pts with advanced solid tumors. The secondary objectives are to estimate the anti-tumor activity and to describe the pharmacokinetics of the combination. Exploratory objectives include assessing predictive and pharmacodynamic markers of response. The study includes a safety lead-in with a 3+3 dose de-escalation design for pts with advanced solid tumors with known tumor TP53 mutation status ( TP53 WT is acceptable) (max 18 pts), followed by expansion cohorts in pts with NSCLC, gastric/GEJ and urothelial cancer (max 100 pts). In expansion, pts with urothelial and gastric cancers must be naïve to anti-PD-1/ L1 therapy. Eprenet is given IV once daily on Days 1–4 while pembro is administered on Day 3 of each 21-day cycle. The RP2D of eprenet+pembro is considered the dose at which ≤ 1 of 6 pts in a cohort has a dose-limiting toxicity (DLT). Primary endpoints are occurrence of DLTs, adverse events (AEs) and serious AEs with eprenet+pembro. Key secondary endpoints are best objective response, progression free survival and overall survival. Exploratory endpoints include gene mutations by next generation sequencing (including TP53), mRNA expression, multiplex immunohistochemistry and transcriptomics, multiplex flow cytometry on peripheral blood mononuclear cells and cytokines in serum. Continuous monitoring of toxicity will be conducted. The trial opened in May 2020 and is actively enrolling patients. Clinical trial information: NCT04383938.

3568 Background: Diets inducing an elevated insulin response have been associated with increased recurrence and mortality in patients with non-metastatic colorectal cancer, but it remains unknown if postprandial hyperinsulinemia also affects progression and mortality in mCRC patients. The goal of this study was to assess the influence of dietary insulin load (DIL) and dietary insulin index (DII) on survival of mCRC patients. Methods: This was a prospective cohort study of 1,177 patients with previously untreated mCRC enrolled in a phase III trial of systemic chemotherapy plus biologics who reported dietary intake within one month after chemotherapy initiation. DIL was calculated as a function of food insulin index and the energy content of individual foods reported on a food frequency questionnaire. DII was calculated by dividing DIL by total energy intake. The primary endpoint was overall survival (OS). Secondary endpoints were progression-free survival (PFS) and treatment-related adverse events (TRAEs). The primary statistical test was a test for trend, which was performed using the median value for each quintile of dietary insulin score as a continuous variable. Cox proportional hazards regression was used to adjust for potential confounders including assigned treatment arm, known prognostic factors, comorbidities, body mass index, and physical activity. Results: Higher DIL was significantly associated with worse OS (ptrend = 0.04); patients in the highest quintile survived 34.1 months, compared to 27.7 months in the lowest quintile (Cox hazard ratio [HR] 1.22, 95% confidence interval [CI] 0.99 - 1.51). Higher DII was non-significantly associated with worse OS (HR 1.18, 95% CI 0.94 - 1.48, ptrend = 0.09). There was no significant association between dietary insulin scores and PFS. The influence of dietary insulin scores on survival did not differ significantly by various molecular markers involved in the insulin signaling pathway, including C-peptide, adiponectin, IGF-1, IGFBP-3, and IGFBP-7. Higher dietary insulin scores were significantly associated with greater risk of any TRAE. Those with a DIL greater than the median had a 75.4% rate of any TRAE, compared to 70.8% in those with a DIL less than or equal to the median (HR 1.19, 95% CI 1.03 - 1.38, p=0.02); the most significant associations were with neutropenia (HR 1.30, 95% CI 1.05 - 1.61, p=0.01) and diarrhea (HR 1.43, 95% CI 1.00 - 2.06, p=0.05). Conclusions: Higher DIL was significantly associated with worse OS, and both higher DIL and DII were significantly associated with increased TRAEs, in patients with previously untreated mCRC. These findings may inform future dietary recommendations for patients with mCRC. Further investigation into the molecular mechanisms underlying these associations is warranted. Clinical trial information: NCT00265850.

Background Although the European Medicines Agency and the US Food and Drug Administration have cleared several devices that use neuromodulation to provide clinical benefits in the acute or preventive treatment of migraine, the Clinical Trials Committee of the International Headache Society has not developed guidelines specifically for clinical trials of neuromodulation devices. In recognition of the distinct needs and challenges associated with their assessment in controlled trials, the Committee provides these recommendations for optimizing the design and conduct of controlled trials of neuromodulation devices for the acute and/or preventive treatment of migraine. Methods An international group of headache scientists and clinicians with expertise in neuromodulation evaluated clinical trials involving neuromodulation devices that have been published since 2000. The Clinical Trials Committee incorporated findings from this expert analysis into a new guideline for clinical trials of neuromodulation devices for the treatment of migraine. Results Key terms were defined and recommendations provided relative to the assessment of neuromodulation devices for acute treatment in adults, preventive treatment in adults, and acute and preventive treatment in children and adolescents. Ethical and administrative responsibilities were outlined, and a bibliography of previous research involving neuromodulation devices was created. Conclusions Adoption of these recommendations will improve the quality of evidence regarding this important area in migraine treatment.

AbstractInformation about the effects of angiotensin II receptor blocker (ARB) therapy on the hemodynamic and cardiac structure in patients with chronic aortic regurgitation (CAR) and isolated systolic hypertension (ISH) is limited.This study planned to test the hypothesis that l-arginine could further enhance the beneficial effect of an ARB, losartan, and provide a favorable effect on the natural history of CAR and ISH.Sixty patients with CAR and ISH were enrolled in a randomized, double-blind trial comparing hemodynamic and ultrasonic change in two treatment arms: losartan + l-arginine and losartan-only treated groups. Serial echocardiographic and hemodynamic studies were evaluated before and after treatment.Both groups had a significant reduction in systolic blood pressure (SBP) and diastolic blood pressure (DBP), left ventricular end-diastolic volume index (LVEDVI), LV end-systolic volume index (LVESVI), LV mass index (LVMI), and LV mean wall stress after 6- and 12-month treatment (p <0.01 in all comparisons). Both groups had a significant increase in LV ejection fraction and exercise duration after 6- and 12-month treatment (p < 0.01 in all comparisons). Using multivariate linear regression analysis, only losartan + l-arginine therapy achieved a significantly lower LVESVI (38.89 ± 0.23 mL/m2), LVEDVI (102.3 ± 0.3 mL/m2), LVMI (107.6 ± 0.3 g/m2), SBP (123.5 ± 1.0 mm Hg), and greater exercise duration (7.38 ± 0.02 minutes) than those of the losartan-only treated groups (p <0.01 in all comparisons).These findings suggest that early co-administrative strategy provides a beneficial approach to favorably influence the natural history of CAR.

Abstract Objectives Flow cytometric detection of T-cell clonality is challenging, particularly in differential diagnosis of immature T-cell proliferations. Studies have shown utility of TRBC1, in conjunction with other T-cell markers, as reliable means to identify T-cell clonality by flow cytometry. One limitation of surface TRBC1 (sTRBC1) evaluation is it cannot be detected in surface CD3 (sCD3)-negative T cells, such as normal or abnormal immature T-cell precursors. Here, we assess surface and cytoplasmic TRBC1 expression patterns in the differential diagnosis of T-lymphoblastic leukemia/lymphoma (T-ALL) vs normal thymocyte expansions. Methods Forty-three samples containing T-ALL, thymoma, normal thymus, and/or indolent T-lymphoblastic proliferation (i-TLBP), were evaluated. Results All 24 cases with normal thymocytes or i-TLBPs revealed a characteristic and reproducible sCD3/sTRBC1 expression pattern indicative of polytypic T-cell maturation. In contrast, all 19 T-ALLs lacked this polytypic maturation pattern and were either completely negative for sCD3/sTRBC1 or showed a minor sCD3-positive subset with a monotypic TRBC1 expression pattern. Cytoplasmic TRBC1 evaluation in 9 T-ALLs demonstrated a monotypic intracellular TRBC1-positive (n = 4) or TRBC1-negative (n = 5) expression, indicative of clonality. Conclusions Our findings demonstrate flow cytometric evaluation of surface and cytoplasmic TRBC1 expression can aid detection of T-cell clonality and differential diagnosis of immature T-cell proliferations.

Abstract Neurodegenerative disorders, such as Alzheimer's disease and Parkinson's disease, are devastating diseases in the elderly world, which are closely associated with progressive neuronal loss induced by a variety of genetic and/or environmental factors. Unfortunately, currently available treatments for neurodegenerative disorders can only relieve the symptoms but not modify the pathological processes. Over the past decades, our group by collaborating with Profs. Yuan‐Ping Pang and Paul R. Carlier has developed three series of homo/hetero dimeric acetylcholinesterase inhibitors derived from tacrine and/or huperzine A. The representative dimers bis(3)‐Cognitin (B3C), bis(12)‐hupyridone, and tacrine(10)‐hupyridone might possess disease‐modifying effects through the modulation of N ‐methyl‐ d ‐aspartic acid receptors, the activation of myocyte enhancer factor 2D gene transcription, and the promotion of neurotrophic factor secretion. In this review, we summarize that the representative dimers, such as B3C, provide neuroprotection against a variety of neurotoxins via multiple targets, including the inhibitions of N ‐methyl‐ d ‐aspartic acid receptor with pathological‐activated potential, neuronal nitric oxide synthase, and β‐amyloid cascades synergistically. More importantly, B3C might offer disease‐modifying potentials by activating myocyte enhancer factor 2D transcription, inducing neuritogenesis, and promoting the expressions of neurotrophic factors in vitro and in vivo. Taken together, the novel dimers might offer synergistic disease‐modifying effects, proving that dimerization might serve as one of the strategies to develop new generation of therapeutics for neurodegenerative disorders. image