In addition to being an inhibitor of ALDH2, 4-hydroxynonenal is also a substrate for ALDH2; at low concentrations, the inhibition of ALDH2 by 4-hydroxynonenal is reversible, but becomes irreversible above 10 μM. 4-To control its own synthesis and improve cellular defenses against oxidative stress, 4-hydroxynonenal can trigger antioxidant defense mechanisms[1]. 4-The byproduct of lipid peroxidation, 4-hydroxynonenal, is genotoxic and mutagenic to bacteria, viruses, and mammalian cells. All four DNA bases are reacted with, but to varying degrees of efficiency: G > C > A > T. The most reliable biomarker of 4-Hydroxynonenal's genotoxic effects is 4-Hydroxynonenal-dG, and these adducts are mostly identified in nucleus DNA. The p53 mutation caused by 4-hydroxynonenal-dG is a well-known illustration of the etiological significance of 4-hydroxynonenal-dG in human malignancies. 4-Hydroxynonenal-dG adducts were shown to form preferentially at codon 249's third base in the p53 gene. This resulted in gene mutation and altered a number of biological processes, such as differentiation, apoptosis, cell cycle arrest, and DNA repair[1].

The expression levels of NADPH oxidase 1 (NOX1), inducible nitric oxide synthase (iNOS), and 4-Hydroxynonenal (4-HNE) are measured in mouse brain tissue 24 hours after fluid percussion injury (FPI). Both wild-type (Nrf2+/+) and Nrf2-deficient (Nrf2-/-) mice exhibit increased expression of 4-Hydroxynonenal following 15 psi injury (moderate injury) in comparison to uninjured Nrf2+/+ and Nrf2-/- mice. Comparing Nrf2-/-KO mice to correspondingly damaged and uninjured Nrf2+/+ WT animals, the expression level of 4-hydroxynonenal is much higher in these animals, in line with the iNOS result[2].

Our preliminary work has revealed that vitamin D receptor (VDR) activation is protective against cisplatin induced acute kidney injury (AKI). Ferroptosis was recently reported to be involved in AKI. Here in this study, we investigated the internal relation between ferroptosis and the protective effect of VDR in cisplatin induced AKI. By using ferroptosis inhibitor ferrostatin-1 and measurement of ferroptotic cell death phenotype in both in vivo and in vitro cisplatin induced AKI model, we observed the decreased blood urea nitrogen, creatinine, and tissue injury by ferrostatin-1, hence validated the essential involvement of ferroptosis in cisplatin induced AKI. VDR agonist paricalcitol could both functionally and histologically attenuate cisplatin induced AKI by decreasing lipid peroxidation (featured phenotype of ferroptosis), biomarker 4-hydroxynonenal (4HNE), and malondialdehyde (MDA), while reversing glutathione peroxidase 4 (GPX4, key regulator of ferroptosis) downregulation. VDR knockout mouse exhibited much more ferroptotic cell death and worsen kidney injury than wild type mice. And VDR deficiency remarkably decreased the expression of GPX4 under cisplatin stress in both in vivo and in vitro, further luciferase reporter gene assay showed that GPX4 were target gene of transcription factor VDR. In addition, in vitro study showed that GPX4 inhibition by siRNA largely abolished the protective effect of paricalcitol against cisplatin induced tubular cell injury. Besides, pretreatment of paricalcitol could also alleviated Erastin (an inducer of ferroptosis) induced cell death in HK-2 cell. These data suggested that ferroptosis plays an important role in cisplatin induced AKI. VDR activation can protect against cisplatin induced renal injury by inhibiting ferroptosis partly via trans-regulation of GPX4[3].

Increased methylglyoxal (MG) formation is associated with diabetes and its complications. In zebrafish, knockout of the main MG detoxifying system Glyoxalase 1, led to limited MG elevation but significantly elevated aldehyde dehydrogenases (ALDH) activity and aldh3a1 expression, suggesting the compensatory role of Aldh3a1 in diabetes. To evaluate the function of Aldh3a1 in glucose homeostasis and diabetes, aldh3a1-/- zebrafish mutants were generated using CRISPR-Cas9. Vasculature and pancreas morphology were analysed by zebrafish transgenic reporter lines. Corresponding reactive carbonyl species (RCS), glucose, transcriptome and metabolomics screenings were performed and ALDH activity was measured for further verification. Aldh3a1-/- zebrafish larvae displayed retinal vasodilatory alterations, impaired glucose homeostasis, which can be aggravated via pdx1 silencing induced hyperglycaemia. Unexpectedly, MG was not altered, but 4-hydroxynonenal (4-HNE), another prominent lipid peroxidation RCS exhibited high affinity with Aldh3a1, was increased in aldh3a1 mutants. 4-HNE was responsible for the retinal phenotype via pancreas disruption induced hyperglycaemia and can be rescued via l-Carnosine treatment. Furthermore, in type 2 diabetic patients, serum 4-HNE was increased and correlated with disease progression. Thus, our data suggest impaired 4-HNE detoxification and elevated 4-HNE concentration as biomarkers but also the possible inducers for diabetes, from genetic susceptibility to the pathological progression[4].

[1]. Zhong H, et al. Role of lipid peroxidation derived 4-hydroxynonenal (4-HNE) in cancer: focusing on mitochondria. Redox Biol. 2015;4:193-9.
[2]. Csala M, et al. On the role of 4-hydroxynonenal in health and disease. Biochim Biophys Acta. 2015 May;1852(5):826-38.
[3]. Bhowmick S, et al. Traumatic brain injury-induced downregulation of Nrf2 activates inflammatory response and apoptotic cell death. J Mol Med (Berl). 2019 Nov 22.
[3]. Cell Death Dis. 2020 Jan 29;11(1):73. doi: 10.1038/s41419-020-2256-z.
[4]. Redox Biol. 2020 Oct;37:101723. doi: 10.1016/j.redox.2020.101723.

4-hydroxynon-2-enal is an enal consisting of non-2-ene having an oxo group at the 1-position and a hydroxy group at the 4-position. It has a role as a human metabolite. It is a hydroxyaldehyde, an enal and a 4-hydroxynonenal.

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4-Hydroxynonenal is a uremic toxin. Uremic toxins can be subdivided into three major groups based upon their chemical and physical characteristics: 1) small, water-soluble, non-protein-bound compounds, such as urea; 2) small, lipid-soluble and/or protein-bound compounds, such as the phenols and 3) larger so-called middle-molecules, such as beta2-microglobulin. Chronic exposure of uremic toxins can lead to a number of conditions including renal damage, chronic kidney disease and cardiovascular disease. 4-Hydroxynonenal (HNE), one of the major end products of lipid peroxidation, has been shown to be involved in signal transduction and available evidence suggests that it can affect cell cycle events in a concentration-dependent manner. glutathione S-transferases (GSTs) can modulate the intracellular concentrations of HNE by affecting its generation during lipid peroxidation by reducing hydroperoxides and also by converting it into a glutathione conjugate. Overexpression of the Alpha class GSTs in cells leads to lower steady-state levels of HNE, and these cells acquire resistance to apoptosis induced by lipid peroxidation-causing agents such as H(2)O(2), UVA, superoxide anion, and pro-oxidant xenobiotics, suggesting that signaling for apoptosis by these agents is transduced through HNE. Cells with the capacity to exclude HNE from the intracellular environment at a faster rate are relatively more resistant to apoptosis caused by H(2)O(2), UVA, superoxide anion, and pro-oxidant xenobiotics as well as by HNE, suggesting that HNE may be a common denominator in mechanisms of apoptosis caused by oxidative stress. Transfection of adherent cells with HNE-metabolizing GSTs leads to transformation of these cells due to depletion of HNE. (A3295).

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Uremic toxins such as 4-Hydroxynonenal are actively transported into the kidneys via organic ion transporters (especially OAT3). Increased levels of uremic toxins can stimulate the production of reactive oxygen species. This seems to be mediated by the direct binding or inhibition by uremic toxins of the enzyme NADPH oxidase (especially NOX4 which is abundant in the kidneys and heart) (A7868). Reactive oxygen species can induce several different DNA methyltransferases (DNMTs) which are involved in the silencing of a protein known as KLOTHO. KLOTHO has been identified as having important roles in anti-aging, mineral metabolism, and vitamin D metabolism. A number of studies have indicated that KLOTHO mRNA and protein levels are reduced during acute or chronic kidney diseases in response to high local levels of reactive oxygen species (A7869).

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As a uremic toxin, this compound can cause uremic syndrome. Uremic syndrome may affect any part of the body and can cause nausea, vomiting, loss of appetite, and weight loss. It can also cause changes in mental status, such as confusion, reduced awareness, agitation, psychosis, seizures, and coma. Abnormal bleeding, such as bleeding spontaneously or profusely from a very minor injury can also occur. Heart problems, such as an irregular heartbeat, inflammation in the sac that surrounds the heart (pericarditis), and increased pressure on the heart can be seen in patients with uremic syndrome. Shortness of breath from fluid buildup in the space between the lungs and the chest wall (pleural effusion) can also be present.

C₉H₁₆O₂

156.22

156.12

C, 69.19; H, 10.32; O, 20.48

75899-68-2

4-Hydroxynonenal-d3;148706-06-3

5283344

Colorless to light yellow liquid

0.9±0.1 g/cm3

275.6±23.0 °C at 760 mmHg

115.2±15.2 °C

0.0±1.3 mmHg at 25°C

1.460

1.85

37.3

CCCCCC(O)/C=C/C=O

JVJFIQYAHPMBBX-FNORWQNLSA-N

InChI=1S/C9H16O2/c1-2-3-4-6-9(11)7-5-8-10/h5,7-9,11H,2-4,6H2,1H3/b7-5+

4-hydroxy-2E-nonenal

4 Hydroxynonenal; HNE;4-Hydroxynonenal; 4-Hydroxy-2-nonenal; 75899-68-2; 4-HNE; 4-hydroxynon-2-enal; (E)-4-hydroxynon-2-enal; trans-4-Hydroxy-2-nonenal; 4-Hydroxy-2,3-nonenal;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~100 mg/mL (~640.12 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (16.00 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 2: ≥ 2.08 mg/mL (13.31 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.08 mg/mL (13.31 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)