Subchronic (90-day) repeated dose oral toxicity study of 2-hydroxybenzylamine acetate in rabbit

Inflammation Biomarker Response to Oral 2-Hydroxybenzylamine (2-HOBA) Acetate in Healthy Humans

Inflammation is associated with the formation of reactive oxygen species (ROS) and the formation of lipid-derived compounds, such as isolevuglandins (IsoLGs), malondialdehyde, 4-hydroxy-nonenal, and 4-oxo-nonenal. The most reactive of these are the IsoLGs, which form covalent adducts with lysine residues and other cellular primary amines leading to changes in protein function, immunogenicity, and epigenetic alterations and have been shown to contribute to a number of inflammatory diseases. 2-Hydroxybenzylamine (2-HOBA) is a natural compound found in buckwheat seeds and reacts with all IsoLG adducts preventing adduct formation with proteins and DNA. Therefore, 2-HOBA is well positioned as an agent for the prevention of inflammatory-prone diseases. In this study, we examined the potential beneficial effects of 2-HOBA on oxidative stress and inflammatory biomarkers in two cohorts of healthy younger and older adults. We utilized the Olink® targeted inflammation panel before and after an oral 15-day treatment regimen with 2-HOBA. We found significant relative changes in the plasma concentration of 15 immune proteins that may reflect the in vivo immune targets of 2-HOBA. Treatment of 2-HOBA resulted in significant increased levels of CCL19, IL-12β, IL-20Rα, and TNFβ, whereas levels of TWEAK significantly decreased. Ingenuity Pathway Analysis identified canonical pathways regulated by the differentially secreted cytokines, chemokines, and growth factors upon 2-HOBA treatment and further points to biofunctions related to the recruitment, attraction, and movement of different immune cell types. In conclusion, 2-HOBA significantly altered the protein biomarkers CCL19, IL-12β, IL-20Rα, TNFβ, and TWEAK, and these may be responsible for the protective effects of 2-HOBA against reactive electrophiles, such as IsoLGs, commonly expressed in conditions of excessive oxidative stress. 2-HOBA has a role as a IsoLG scavenger to proactively improve immune health in a variety of conditions.

Electrophilic reactive aldehydes as a therapeutic target in colorectal cancer prevention and treatment

Colorectal cancer (CRC) is a major health problem worldwide. Dicarbonyl electrophiles, such as isolevuglandins (isoLGs), are generated from lipid peroxidation and form covalent adducts with amine-containing macromolecules. We have shown high levels of adducts of isoLGs in colonic epithelial cells of patients with CRC. We thus investigated the role of these reactive aldehydes in colorectal cancer development. We found that 2-hydroxybenzylamine (2-HOBA), a natural compound derived from buckwheat seeds that acts as a potent scavenger of electrophiles, is bioavailable in the colon of mice after supplementation in the drinking water and does not affect the colonic microbiome. 2-HOBA reduced the level of isoLG adducts to lysine as well as tumorigenesis in models of colitis-associated carcinogenesis and of sporadic CRC driven by specific deletion of the adenomatous polyposis coli gene in colonic epithelial cells. In parallel, we found that oncogenic NRF2 activation and signaling were decreased in the colon of 2-HOBA-treated mice. Additionally, the growth of xenografted human HCT116 CRC cells in nude mice was significantly attenuated by 2-HOBA supplementation. In conclusion, 2-HOBA represents a promising natural compound for the prevention and treatment of CRC.

The nutraceutical electrophile scavenger 2-hydroxybenzylamine (2-HOBA) attenuates gastric cancer development caused by Helicobacter pylori

Stomach cancer is a leading cause of cancer death. Helicobacter pylori is a bacterial gastric pathogen that is the primary risk factor for carcinogenesis, associated with its induction of inflammation and DNA damage. Dicarbonyl electrophiles are generated from lipid peroxidation during the inflammatory response and form covalent adducts with amine-containing macromolecules. 2-hydroxybenzylamine (2-HOBA) is a natural compound derived from buckwheat seeds and acts as a potent scavenger of reactive aldehydes. Our goal was to investigate the effect of 2-HOBA on the pathogenesis of H. pylori infection. We used transgenic FVB/N insulin-gastrin (INS-GAS) mice as a model of gastric cancer. First, we found that 2-HOBA is bioavailable in the gastric tissues of these mice after supplementation in the drinking water. Moreover, 2-HOBA reduced the development of gastritis in H. pylori-infected INS-GAS mice without affecting the bacterial colonization level in the stomach. Further, we show that the development of gastric dysplasia and carcinoma was significantly reduced by 2-HOBA. Concomitantly, DNA damage were also inhibited by 2-HOBA treatment in H. pylori-infected mice. In parallel, DNA damage was inhibited by 2-HOBA in H. pylori-infected gastric epithelial cells in vitro. In conclusion, 2-HOBA, which has been shown to be safe in human clinical trials, represents a promising nutritional compound for the chemoprevention of the more severe effects of H. pylori infection.

Salts of 2-hydroxybenzylamine with improvements on solubility and stability: Virtual and experimental screening

2-Hydroxybenzylamine (2-HOBA) is a drug used to effectively treat oxidative stress. To improve its aqueous solubility and thermal stability, salt screening and synthesis was carried out. The conductor-like screening model for the real solvents model (COSMO-RS) was applied to virtual screening of coformers among 200 commonly used candidates for salification of 2-HOBA. As a result, 40 hit compounds were subjected to experimental liquid-assisted grinding (LAG) with 2-HOBA, then 21 systems were characterized as new solid phases by PXRD. Nine multicomponent single crystals of 2-HOBA with succinic acid, p-aminobenzoic acid, p-nitrobenzoic acid, o-nitrobenzoic acid, p-toluic acid, 2,3-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, p-nitrophenol, and 5-hydroxyisophthalic acid were obtained and characterized by single-crystal X-ray diffraction, powder X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. All of them were salts and exhibited higher decomposition temperatures compared with pure 2-HOBA. The apparent aqueous solubility of three new salts, i.e., those with succinic acid, p-aminobenzoic acid, and p-nitrophenol were higher than the equilibrium solubility of 2-HOBA. The accelerated stability test indicated that all salts show excellent stability under conditions (40 °C and 75% RH) for 4 weeks. Overall, this work introduced a protocol that combined the virtual screening tool based on the COSMO-RS model and the experimental LAG method to screen new salts for a target compound. The feasibility of this protocol was confirmed in the case of 2-HOBA whose new salts were successfully obtained and represented an improvement for aqueous solubility and thermal stability.

Scavenging Reactive Lipids to Prevent Oxidative Injury

Oxidative injury due to elevated levels of reactive oxygen species is implicated in cardiovascular diseases, Alzheimer's disease, lung and liver diseases, and many cancers. Antioxidant therapies have generally been ineffective at treating these diseases, potentially due to ineffective doses but also due to interference with critical host defense and signaling processes. Therefore, alternative strategies to prevent oxidative injury are needed. Elevated levels of reactive oxygen species induce lipid peroxidation, generating reactive lipid dicarbonyls. These lipid oxidation products may be the most salient mediators of oxidative injury, as they cause cellular and organ dysfunction by adducting to proteins, lipids, and DNA. Small-molecule compounds have been developed in the past decade to selectively and effectively scavenge these reactive lipid dicarbonyls. This review outlines evidence supporting the role of lipid dicarbonyls in disease pathogenesis, as well as preclinical data supporting the efficacy of novel dicarbonyl scavengers in treating or preventing disease.

Safety, tolerability, and pharmacokinetics of repeated oral doses of 2-hydroxybenzylamine acetate in healthy volunteers: a double-blind, randomized, placebo-controlled clinical trial

BACKGROUND

2-Hydroxybenzylamine (2-HOBA) is a selective dicarbonyl electrophile scavenger being developed as a nutritional supplement to help protect against the development of conditions associated with dicarbonyl electrophile formation, such as the cognitive decline observed with Mild Cognitive Impairment or Alzheimer's disease.

METHODS

This study evaluated the safety, tolerability, and pharmacokinetics of repeated oral doses of 2-HOBA acetate (500 or 750 mg) administered to healthy volunteers every eight hours for two weeks. The effects of 2-HOBA on cyclooxygenase function and cerebrospinal fluid penetrance of 2-HOBA were also investigated.

RESULTS

Repeated oral administration of 2-HOBA was found to be safe and well-tolerated up to 750 mg TID for 15 days. 2-HOBA was absorbed within 2 h of administration, had a half-life of 2.10-3.27 h, and an accumulation ratio of 1.38-1.52. 2-HOBA did not interfere with cyclooxygenase function and was found to be present in cerebrospinal fluid 90 min after dosing.

CONCLUSIONS

Repeated oral administration of 2-HOBA was found to be safe and well-tolerated. These results support continued development of 2-HOBA as a nutritional supplement.

TRIAL REGISTRATION

Studies are registered at ClinicalTrials.gov (NCT03555682 Registered 13 June 2018, NCT03554096 Registered 12 June 18).

Isolevuglandins as mediators of disease and the development of dicarbonyl scavengers as pharmaceutical interventions

Products of lipid peroxidation include a number of reactive lipid aldehydes such as malondialdehyde, 4-hydroxy-nonenal, 4-oxo-nonenal, and isolevuglandins (IsoLGs). Although these all contribute to disease processes, the most reactive are the IsoLGs, which rapidly adduct to lysine and other cellular primary amines, leading to changes in protein function, cross-linking and immunogenicity. Their rapid reactivity means that only IsoLG adducts, and not the unreacted aldehyde, can be readily measured. This high reactivity also makes it challenging for standard cellular defense mechanisms such as aldehyde reductases and oxidases to dispose of them before they react with proteins and other cellular amines. This led us to seek small molecule primary amines that might trap and inactivate IsoLGs before they could modify cellular proteins or other endogenous cellular amines such as phosphatidylethanolamines to cause disease. Our studies identified 2-aminomethylphenols including 2-hydroxybenzylamine as IsoLG scavengers. Subsequent studies showed that they also trap other lipid dicarbonyls that react with primary amines such as 4-oxo-nonenal and malondialdehyde, but not hydroxyalkenals like 4-hydroxy-nonenal that preferentially react with soft nucleophiles. This review describes the use of these 2-aminomethylphenols as dicarbonyl scavengers to assess the contribution of IsoLGs and other amine-reactive lipid dicarbonyls to disease and as therapeutic agents.

First-in-human study assessing safety, tolerability, and pharmacokinetics of 2-hydroxybenzylamine acetate, a selective dicarbonyl electrophile scavenger, in healthy volunteers

Background

2-Hydroxybenzylamine (2-HOBA) is a selective scavenger of dicarbonyl electrophiles that protects proteins and lipids from being modified by these electrophiles. It is currently being developed for use as a nutritional supplement to help maintain good health and protect against the development of conditions associated with dicarbonyl electrophile formation, such as the cognitive decline associated with Mild Cognitive Impairment and Alzheimer’s disease.

Methods

In this first-in-human study, the safety, tolerability, and pharmacokinetics of six ascending single oral doses of 2-HOBA acetate were tested in eighteen healthy human volunteers.

Results

Reported adverse events were mild and considered unlikely to be related to 2-HOBA. There were no clinically significant changes in vital signs, ECG recordings, or clinical laboratory parameters. 2-HOBA was fairly rapidly absorbed, with a t_max of 1–2 h, and eliminated, with a t_1/2 of approximately 2 h. Both t_max and t_1/2 were independent of dose level, while C_max and AUC increased proportionally with dose level.

Conclusions

2-HOBA acetate was safe and well-tolerated at doses up to 825 mg in healthy human volunteers, positioning it as a good candidate for continued development as a nutritional supplement.

Trial registration

This study is registered at ClinicalTrials.gov (NCT03176940).

Electronic supplementary material

The online version of this article (10.1186/s40360-018-0281-7) contains supplementary material, which is available to authorized users.