AB0038 DUAL TARGETING PEPTIDE RLS-0071 REDUCES AND INHIBITS MYELOPEROXIDASE (MPO) IN HEALTHY HUMAN VOLUNTEER

Background

RLS-0071-101 was a first in human clinical trial to evaluate safety of the peptide RLS-0071 in healthy volunteers in a single ascending dose and multiple ascending dose format. RLS-0071, previously referred to as Peptide Inhibitor of Complement C1 (PIC1) is a dual-targeting peptide being developed for clinical use to moderate humoral and cellular inflammation via inhibition of complement activation and neutrophil effectors including myeloperoxidase (MPO) and Neutrophil extracellular trap formation (NETosis).1,2 Humans that are otherwise asymptomatic are considered at risk for cardiovascular complications if they have a plasma MPO level of > 420 pmol.3 A post hoc analysis of plasma samples from subjects participating in RLS-0071-101 identified an individual with mildly elevated baseline MPO level (142 pmol/L).

Objectives

Evaluate if RLS-0071 dosing would change MPO level or activity in a subject with elevated baseline MPO.

Methods

Frozen plasma samples prepared from blood collected by venipunture into K2EDTA tubes (BD) was utilized to determine MPO quantity and activity levels. MPO quantity in the plasma was analyzed using a human MPO ELISA kit (BMS2038INST, Invitrogen) and MPO activity within the plasma was analyzed using a fluorescence-based myeloperoxidase assay kit (K745-100, BioVision).

Results

Upon screening 54 subjects from RLS-0071-101 we identified one individual with a mildly elevated MPO level at baseline, a 21-year-old white female with BMI of 21.7. The subject received 9 intravenous infusions of RLS-0071 each at a dose of 10 mg/kg. Her vital signs and body temperature remained normal throughout the study and the only blood laboratory abnormality were a mildly low plasma protein concentration of Day 2 and Day 4 which was noted both among recipients of the peptide and placebo subjects. Analysis of MPO blood concentrations demonstrated a mildly elevated baseline plasma MPO concentration that decreased after multiple doses of RLS-0071 with partial recovery to baseline 24 hours after cessation of dosing. MPO activity analyzed using a fluorescence-based myeloperoxidase assay kit demonstrated an elevated baseline plasma MPO activity level that decreased after multiple doses of RLS-0071 with partial recovery after 24 hours.

Conclusion

These results suggest promise for RLS-0071 to reversibly moderate plasma MPO activity and potentially affect MPO-mediated diseases including acute coronary syndrome (ACS), atheromatous plaque vulnerability and auto immune conditions.4,5,6,7.

References

[1]Sharp, Julia A., et al. “Peptide inhibitor of complement c1, a novel suppressor of classical pathway activation: mechanistic studies and clinical potential.” Frontiers in immunology 5 (2014): 406.

[2]Hair, Pamela S., et al. “Inhibition of myeloperoxidase activity in cystic fibrosis sputum by peptide inhibitor of complement C1 (PIC1).” PLoS One 12.1 (2017): e0170203.

[3]Tang WH, Wu Y, Nicholls SJ, Hazen SL. Plasma myeloperoxidase predicts incident cardiovascular risks in stable patients undergoing medical management for coronary artery disease. Clin Chem. 2011;57(1):33-9.

[4]Malle, E.; Marsche, G.; Panzenboeck, U.; Sattler, W. Myeloperoxidase-mediated oxidation of high-density lipoproteins: Fingerprints of newly recognized potential proatherogenic lipoproteins. Arch. Biochem. Biophys., 2006, 445 (2), 245-255.

[5]Nurcombe, H. L.; Bucknall, R. C.; Edwards, S. W. Activation of the neutrophil myeloperoxidase-H2O2 system by synovial fluid isolated from patients with rheumatoid arthritis. Ann. Rheum. Dis., 1991, 50 (4), 237-242

[6]Malle, E.; Buch, T.; Grone, H. J. Myeloperoxidase in kidney disease. Kidney Int., 2003, 64 (6), 1956-1967.

[7]Nicholls, S. J.; Hazen, S. L. Myeloperoxidase and cardiovascular disease. Arterioscler., Thromb., Vasc. Biol., 2005, 25 (6), 1102- 1111.

Disclosure of Interests

Parvathi Kumar Shareholder of: I have stock options available, Consultant of: Served as a consultant for ReAlta life Sciences INC from April- July 2020, Employee of: I am employed by ReAlta Life Sciences, Kenji Cunnion Shareholder of: Shareholder of ReAlta life sciences, Employee of: ReAlta Life Sciences, Neel Krishna Employee of: I am an employee of ReAlta Life Sciences., Ulrich Thienel Shareholder of: Shareholder of ReAlta and JNJ, Employee of: ReAlta Life Sciences, Pamela Hair Employee of: ReAlta Life Sciences, Jessica Goss Employee of: ReAlta Life Sciences, Christos Gabriel: None declared

The impact of state laws on motor vehicle fatality rates, 1999-2015

BACKGROUND

Motor vehicle crash (MVC) fatalities have been declining while states passed various legislation targeting driver behaviors. This study assesses the impact of state laws on MVC fatality rates to determine which laws were effective.

METHODS

Publically available data were collected on driver-related motor vehicle laws, law strengths, enactment years, and numbers of verified-trauma centers. Prospective data on crash characteristics and MVC fatalities 16 years or older from Fatality Analysis Reporting System 1999 to 2015 (n = 850) were obtained. Generalize Linear Autoregressive Modeling was used to assess the relative contribution of state laws to the crude MVC fatality rate while controlling for other factors.

RESULTS

Lowering the minimum blood alcohol content (BAC) was associated with largest declines for all ages, especially the older cohorts: 16 years to 20 years (B = 0.23; p < 0.001), 21 years to 55 years (B = 1.7; p < 0.001); 56 years to 65 years (B = 3.2; p < 0.001); older than 65 years (B = 4.1; p < 0.001). Other driving under the influence laws were also significant. Per se BAC laws accompanying a reduced BAC further contributed to declines in crude fatality rates: 21 years to 55 years (B = -0.13; p < 0.001); older than 65 years (B = -0.17; p < 0.05). Driving under the influence laws enhancing the penalties, making revocation automatic, or targeting social hosts had mixed effects by age. Increased enforcement, mandatory education, vehicle impoundment, interlock devices, and underage alcohol laws showed no association with declining mortality rates. Red light camera and seatbelt laws were associated with declines in mortality rates for all ages except for older than 65 years cohort, but speed camera laws had no effect. Graduated Driver License laws were associated with declines for 16 years to 21 years (B = -0.06; p < 0.001) only. Laws targeting specific risks (elderly, motorcycles, marijuana) showed no effect on declining MVC mortality rates during the study period.

CONCLUSION

States have passed a wide variety of laws with varying effectiveness. A few key laws, specifically laws lowering allowable BAC, implementing red light cameras, and mandating seatbelt use significantly reduced MVC mortality rates from 1999 to 2015. Simply adding more laws/penalties may not equate directly to lives saved. Continued research on state laws will better inform policy makers to meet evolving public health needs in the management of MVC fatalities.

LEVEL OF EVIDENCE

Epidemiological, Level III.

Adherence to APSA activity restriction guidelines and 60-day clinical outcomes for pediatric blunt liver and splenic injuries (BLSI)

BACKGROUND

After NOM for BLSI, APSA guidelines recommend activity restriction for grade of injury +2 in weeks. This study evaluates activity restriction adherence and 60 day outcomes.

METHODS

Non-parametric tests and logistic regression were utilized to assess difference between adherent and non-adherent patients from a 3-year prospective study of NOM for BLSI (≤18 years).

RESULTS

Of 1007 children with BLSI, 366 patients (44.1%) met the inclusion criteria of a completed 60 day follow-up; 170 (46.4%) had liver injury, 159 (43.4%) had spleen injury and 37 (10.1%) had both. Adherence to recommended activity restriction was claimed by 279 (76.3%) patients; 49 (13.4%) reported non-adherence and 38 (10.4%) patients had unknown adherence. For 279 patients who adhered to activity restrictions, unplanned return to the emergency department (ED) was noted for 35 (12.5%) with 16 (5.7%) readmitted; 202 (72.4%) returned to normal activity by 60 days. No patient bled after discharge. There was no statistical difference between adherent patients (n = 279) and non-adherent (n = 49) for return to ED (χ2 = 0.8 [p < 0.4]) or readmission (χ2 = 3.0 [p < 0.09]); for 216 high injury grade patients, there was no difference between adherent (n = 164) and non-adherent (n = 30) patients for return to ED (χ2 = 0.6 [p < 0.4]) or readmission (χ2 = 1.7 [p < 0.2]).

CONCLUSION

For children with BLSI, there was no difference in frequencies of bleeding or ED re-evaluation between patients adherent or non-adherent to the APSA activity restriction guideline.

LEVEL OF EVIDENCE

Level II, Prognosis.

Importance of papillary muscle infarction detected by cardiac magnetic resonance imaging in predicting cardiovascular events

BACKGROUND

Recent studies suggest that papillary muscle infarction (PMI) following recent myocardial infarction (MI) correlates with adverse cardiovascular outcomes. The purpose of this study is to determine the prevalence and prognostic significance of PMI by cardiac magnetic resonance (CMR) in a large cohort of patients.

METHODS

Retrospective study of patients who underwent CMR between January 2007 and December 2009 were evaluated for the presence of PMI in one or both of the left ventricle papillary muscles. The primary outcome was a time to a combined endpoint of all-cause mortality and worsening heart failure. Secondary outcomes were time to individual components of the combined outcome.

RESULTS

419 patients were included in our analysis, 232 patients (55%) had ischemic cardiomyopathy. Patients were followed at six-month intervals for a median follow-up time of 3.7 (interquartile range (IQR): 1.6; 6.3) years after initial imaging. During this period 196 patients (46.8%) had a primary outcome and 92 patients (22%) died. PM infarct was identified in 204 (48.7%) patients with twice as many posteromedial (PRM) (27%) than anterolateral (ARL) lesions (11%) and a similar number with infarct in both (11%). There was no association between studied outcomes and the presence of PMI in either PRM or ARL PM. The presence of infarct in both PM was a predictor of both the primary outcome (HR 1.69, CI[1.01-2.86], p<0.049.) and mortality (HR 1.69, CI[1.01-4.2], p<0.046).

CONCLUSION

The presence of infarct in either papillary muscle was not associated with outcomes. However, infarct involving both papillary muscles was associated with worse outcomes.

STIM1 overexpression promotes colorectal cancer progression, cell motility and COX-2 expression

Tumor metastasis is the major cause of death among cancer patients, with more than 90% of cancer-related death attributable to the spreading of metastatic cells to secondary organs. Store-operated Ca²⁺ entry (SOCE) is the predominant Ca²⁺ entry mechanism in most cancer cells, and STIM1 is the endoplasmic reticulum (ER) Ca²⁺ sensor for store-operated channels (SOC). Here we reported that the STIM1 was overexpressed in colorectal cancer (CRC) patients. STIM1 overexpression in CRC was significantly associated with tumor size, depth of invasion, lymphnode metastasis status and serum levels of carcinoembryonic antigen. Furthermore, ectopic expression of STIM1 promoted CRC cell motility, while depletion of STIM1 with shRNA inhibited CRC cell migration. Our data further suggested that STIM1 promoted CRC cell migration through increasing the expression of cyclooxygenase-2 (COX-2) and production of prostaglandin E2 (PGE2). Importantly, ectopically expressed COX-2 or exogenous PGE2 were able to rescue migration defect in STIM1 knockdown CRC cells, and inhibition of COX-2 with ibuprofen and indomethacin abrogated STIM1-mediated CRC cell motility. In short, our data provided clinicopathological significance for STIM1 and store-operated Ca²⁺ entry in CRC progression, and implicated a role for COX-2 in STIM1-mediated CRC metastasis. Our studies also suggested a new approach to inhibit STIM1-mediated metastasis with COX-2 inhibitors.

Subclinical pulmonary dysfunction in spinocerebellar ataxias 1, 2 and 3

OBJECTIVES

Evaluation of pulmonary function in patients with spinocerebellar ataxias (SCA) 1, 2 and 3 without clinical evidence of pulmonary dysfunction.

METHODS

Thirty patients (F:M = 7:23; age: 35 ± 11.3 years; SCA1 - 13, SCA2 - 9 and SCA3 - 8) without clinical manifestations of respiratory dysfunction and 30 controls underwent pulmonary function tests. The percentage predicted values of forced vital capacity (FVC), volume of air exhaled during first second of FVC (FEV1), peak expiratory flow rate (PEFR) and maximal voluntary ventilation (MVV), actual values of maximal inspiratory and expiratory pressures (MIP and MEP in mmHg), and ratios of actual values of FEV1/FVC (%) and FEV1/PEFR (ml/l/min) were analyzed.

RESULTS

Compared with controls SCA patients had significant reductions of FVC (71.1 ± 17.5 vs 85.5 ± 18.7; P < 0.01), PEFR (51.5 ± 20.7 vs 77.1 ± 24.9; P < 0.001), MVV (64.4 ± 21.6 vs 97.2 ± 22.7; P < 0.001), MIP (27.7 ± 16.8 vs 50.1 ± 15.1; P < 0.001) and MEP (38.1 ± 18.7 vs 74.7 ± 16.0; P < 0.001), elevation of FEV1/PEFR (10.5 ± 2.8 vs 7.4 ± 2.1; P < 0.001), but no significant change of FEV1 and FEV1/FVC. FEV1/PEFR correlated positively with illness duration and MVV negatively with severity of illness.

CONCLUSIONS

The present study showed subclinical restrictive type of pulmonary dysfunction in SCA, and possible presence of upper airway obstruction. Chest physiotherapy and breathing exercises should be introduced early in management of SCA.

A new sphingolipid from the gorgonianjunceella junceaof the Indian ocean

A new sphingolipid, (2S,3R,4E)-1,3-dihydroxy-2-[(nonadecanoyl) amino]-octadec-4-ene (1) along with ubiquitous batyl alcohol is isolated from the gorgonian, Junceella juncea Pallas (Gorgonaceae) of the Indian Ocean. The structure of 1 is determined on the basis of 1H- and 13C-NMR, COSY, FABMS, and GC-EIMS experiments.

New sphingosines from a gorgonian, Pseudopterogorgia australiensis Ridley, of the Indian Ocean

Two new sphingosines, (2S,3R)-2-(docosanoyl amino)nonadecane-1,3-diol (1) and (2S,3S,4R)-2-[(2'R)-2'-hydroxynonadecanoylamino]nonadecane-1,3,4-triol (3), along with the known (2S,3R,4E)-2-(heptadecanoylamino)octadec-4-ene-1,3-diol, have been isolated from Pseudopterogorgia australiensis, of the Indian Ocean. The structures were deduced from spectral and chemical methods. Compounds 1-3 showed moderate antibacterial activity.

Expression of DnaK and GroEL homologs in Leuconostoc esenteroides in response to heat shock, cold shock or chemical stress

The mechanism of adaptation of bacteria to survive at elevated temperature in the human host and the expression of heat-shock proteins in response to stress was examined by labelling with [35S]methionine. An increase in culture temperature from 26 degrees C to 37 degrees C induced expression of certain bacterial proteins (70 and 60 kDa). Heat shock at 40 degrees C, cold shock (10 degrees C), ethanol treatment or arsenite treatment also led to an increased expression of heat shock proteins of 70 and 60 kDa. Actinomycin D completely blocked the induction, indicating that transcription is required for the overexpression of stress proteins in Leuconostoc mesenteroides. N-terminal sequence analysis showed that these proteins were homologous to the highly conserved chaperone proteins DnaK and GroEL of Escherichia coli, respectively.

Excessive ingestion of fluoride and the significance of sialic acid: glycosaminoglycans in the serum of rabbit and human subjects

The levels of sialic acid and glycosaminoglycans were explored in the sera of rabbit and human subjects who ingested fluoride and had clinical manifestation of fluorosis. Changes observed in the level of these chemical constituents in sera possibly reflect changes occurring in calcified and noncalcified tissues due to fluoride intoxication. The ratio of sialic acid content vs glycosaminoglycans revealed there was a 50% reduction in rabbit and human sera. The test is recommended for evaluating the prognosis of fluoride poisoning/fluorosis.