Endogenous Metabolite

5-Aminolevulinic acid (5-ALA) upregulates genes associated to defense and immunity, improves aerobic energy metabolism, and strengthens Penaeus vannamei's immunological response to Vibrio parahaemolyticus [1].

With the emergence of several infectious diseases in shrimp aquaculture, there is a growing interest in the use of feed additives to enhance shrimp immunity. Recently, the use of 5-aminolevulinic acid (5-ALA), a non-protein amino acid that plays a rate-limiting role in heme biosynthesis, has received attention for its positive effect on immunity in livestock animals. To evaluate the effect of 5-ALA in the Pacific white shrimp, Litopenaeus vannamei, we conducted microarray analysis, a Vibrio parahaemolyticus immersion challenge test, an ATP level assay, and gene expression analysis of some hemoproteins and genes associated with heme synthesis and degradation. Out of 15,745 L. vannamei putative genes on the microarray, 101 genes were differentially expressed by more than fourfold (p < 0.05) between 5-ALA-supplemented and control shrimp hepatopancreas. 5-ALA upregulated 99 of the 101 genes, 41 of which were immune- and defense-related genes based on sequence homology. Compared to the control, the 5-ALA-supplemented group had a higher survival rate in the challenge test, higher transcript levels of porphobilinogen synthase, ferrochelatase, catalase, nuclear receptor E75, and heme oxygenase-1 and higher levels of ATP. These findings suggest that dietary 5-ALA enhanced the immune response of L. vannamei to V. parahaemolyticus, upregulated immune- and defense-related genes, and enhanced aerobic energy metabolism, respectively. Further studies are needed to elucidate the extent of 5-ALA use in shrimp culture[1].

Expression of GPX4 and HMOX1 in pathologic specimens of 97 ESCC patients was examined, and prognostic analyses were performed. Real-time polymerase chain reaction (RT-PCR), RNA microarray, and Western blotting analyses were used to evaluate the role of 5-ALA in ferroptosis in vitro. Ann Surg Oncol. 2021 Jul;28(7):3996-4006. https://pubmed.ncbi.nlm.nih.gov/33210267/

Tumor volumetry was performed immediately prior to surgery. Tumor resection was then performed using the 5-ALA signal alone with the absence of a visible signal defining completeness of resection. This determination was carried out by the primary surgeon at all times. Functional neuronavigation data was intermittently projected to prevent inadvertent damage to functional brain areas. At the end of each stage of resection, the tumor cavity was systematically inspected to exclude residual tumor. Once the 5-ALA signal was undetectable, an iMRI scan was performed. If the extent of resection was confirmed, the decision to conclude the surgery was taken by the primary surgeon. Otherwise, the residual tumor volume was re-segmented and resection continued according to the neuronavigation. In all such cases the 5-ALA signal was redetected during further surgery once either the thin intervening layer of “healthy” brain parenchyma was removed and/or the viewing angle subsequently optimized. This procedure was repeated until the 5-ALA signal was no longer detectable, and the corresponding absence of contrast-enhancing tumor corroborated by iMRI. The additionally resected tissue detected by the iMRI was also analyzed by an experienced neuropathologist, confirming pathological glioma cell infiltration. In the event of persistence of 5-ALA in areas shown to be functional by the neuronavigation data, further surgery in the corresponding direction was intentionally terminated. PLoS One, 2012. 7(9): p. e44885.

Absorption, Distribution and Excretion
Oral bioavailability is 50-60%. ### **Topical gel** Pharmacokinetics (PK) of aminolevulinic acid (ALA) and PpIX was evaluated in a trial of 12 adult subjects with mild to moderate AK with at least 10 AK lesions on the face or forehead. A single dose of one entire tube of ALA (2 grams) was applied under occlusion for 3 hours followed by photodynamic therapy (PDT) to a total area of 20 cm2. The mean ± SD baseline plasma ALA and PpIX concentrations were 20.16 ± 16.53 ng/mL and 3.27 ± 2.40 ng/mL, respectively. In most subjects, an up to 2.5-fold increase of ALA plasma concentrations was observed during the first 3 hours after ALA application. The mean ± SD area under the concentration time curve (AUC0-t) and maximum concentration (Cmax) for baseline corrected ALA (n=12) were 142.83 ± 75.50 ng.h/mL and 27.19 ± 20.02 ng/mL, respectively. The median Tmax (time at which Cmax occurred) was 3 hours. ### **Topical solution** Two human pharmacokinetic (PK) studies were conducted in subjects with minimally to moderately thick actinic keratoses on the upper extremities, having at least 6 lesions on one upper extremity and at least 12 lesions on the other upper extremity. A single dose comprising of two topical applications of ALA topical solution (each containing 354 mg ALA HCl) were directly applied to the lesions and occluded for 3 hours prior to light treatment. The first PK study was conducted in 29 subjects and PK parameters of ALA were assessed. The baseline corrected mean ± SD of the maximum concentration (Cmax) of ALA was 249.9 ± 694.5 ng/mL and the median Tmax was 2 hours post dose. The mean ± SD exposure to ALA, as expressed by area under the concentration time curve (AUCt) was 669.9 ± 1610 ng·hr/mL. The mean ± SD elimination half-life (t1/2) of ALA was 5.7 ± 3.9 hours. A second PK study was conducted in 14 subjects and PK parameters of ALA and PpIX were measured. The baseline corrected PpIX concentrations were negative in at least 50% of samples in 50% (7/14) subjects and AUC could not be estimated reliably. The baseline-corrected mean ± SD of Cmax for ALA and PpIX was 95.6 ± 120.6 ng/mL and 0.95 ± 0.71 ng/mL, respectively. The median Tmax of ALA and PpIX was 2 hours post dose and 12 hours post dose, respectively. The mean AUCt of ALA was 261.1 ± 229.3 ng·hr/mL. The mean ± SD t1/2 of ALA was 8.5 ± 6.7 hours. ### **Oral solution** In 12 healthy subjects, the absolute bioavailability of ALA following the recommended dose of ALA solution was 100.0% + 1.1 with a range of 78.5% to 131.2%. Maximum ALA plasma concentrations were reached with a median of 0.8 hour (range 0.5 – 1.0 hour).
In 12 healthy subjects, excretion of parent aminolevulinic acid (ALA) in urine in the 12 hours following administration of the recommended dose of ALA solution was 34 + 8% (mean + std dev) with a range of 27% to 57%.
In healthy volunteers, the administration of aminolevulinic acid resulted in a volume of distribution of 9.3 ± 2.8 L intravenously and 14.5 ± 2.5 orally.[11961050]

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Metabolism / Metabolites
Exogenous aminolevulinic acid (ALA) is metabolized to PpIX, but the fraction of administered ALA that is metabolized to PpIX is unknown. The average plasma AUC of PpIX is less than 6% of that of ALA.
Following topical administration, synthesis into protoporphyrin IX takes place in situ in the skin.
Half Life: Mean half-life is 0.70 ± 0.18 h after the oral dose and 0.83 ± 0.05 h after the intravenous dose.

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Biological Half-Life
The mean ± SD elimination half-life (t_1/2) of aminolevulinic acid was 5.7 ± 3.9 hours for the topical solution formulation and the mean half-life was 0.9 ± 1.2 hours for the oral solution formulation. In another pharmacokinetic studies with 6 healthy volunteers using a 128 mg dose, the mean half-life was 0.70 ± 0.18 h after the oral dose and 0.83 ± 0.05 h after the intravenous dose.

Toxicity Summary
According to the presumed mechanism of action, photosensitization following application of aminolevulinic acid (ALA) topical solution occurs through the metabolic conversion of ALA to protoporphyrin IX (PpIX), which accumulates in the skin to which aminolevulinic acid has been applied. When exposed to light of appropriate wavelength and energy, the accumulated PpIX produces a photodynamic reaction, a cytotoxic process dependent upon the simultaneous presence of light and oxygen. The absorption of light results in an excited state of the porphyrin molecule, and subsequent spin transfer from PpIX to molecular oxygen generates singlet oxygen, which can further react to form superoxide and hydroxyl radicals. Photosensitization of actinic (solar) keratosis lesions using aminolevulinic acid, plus illumination with the BLU-UTM Blue Light Photodynamic Therapy Illuminator (BLU-U), is the basis for aminolevulinic acid photodynamic therapy (PDT).

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Effects During Pregnancy and Lactation
◉ Summary of Use during Lactation
No information is available on the use of oral aminolevulinic acid during breastfeeding. To minimize exposure of the infant, breastfeeding can be withheld for 24 hours after an oral dose. Breastfeeding is not expected to result in exposure of the child to topical aminolevulinic acid due to negligible systemic absorption. Aminolevulinic acid-induced photodynamic therapy has been used successfully to treat various skin lesions of the nipple. This treatment appeared to preserve nipple anatomy for breastfeeding.
◉ Effects in Breastfed Infants
Relevant published information was not found as of the revision date.
◉ Effects on Lactation and Breastmilk
Relevant published information was not found as of the revision date.

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Protein Binding
In in vitro experiments using aminolevulinic acid (ALA) concentrations up to approximately 25% of the maximal concentration that occurs in plasma following the recommended dose of ALA solution, the mean protein binding of ALA was 12%.

[1]. Effects of 5-Aminolevulinic Acid on Gene Expression, Immunity, and ATP Levels in Pacific White Shrimp, Litopenaeus vannamei. Mar Biotechnol (NY). 2018 Aug 25.

Pharmacodynamics
The metabolism of aminolevulinic acid (ALA) is the first step in the biochemical pathway resulting in heme synthesis. Aminolevulinic acid is not a photosensitizer, but rather a metabolic precursor of protoporphyrin IX (PpIX), which is a photosensitizer. The synthesis of ALA is normally tightly controlled by feedback inhibition of the enzyme, ALA synthetase, presumably by intracellular heme levels. ALA, when provided to the cell, bypasses this control point and results in the accumulation of PpIX, which is converted into heme by ferrochelatase through the addition of iron to the PpIX nucleus.

C5H9NO3

131.12986

131.058

C, 45.80; H, 6.92; N, 10.68; O, 36.60

106-60-5

5-Aminolevulinic acid hydrochloride;5451-09-2;5-Aminolevulinic acid-13C;123253-93-0

137

Typically exists as solid at room temperature

1.2±0.1 g/cm3

298.4±20.0 °C at 760 mmHg

156-158 °C
156 - 158 °C

134.3±21.8 °C

0.0±1.3 mmHg at 25°C

1.482

-0.93

2

4

4

9

121

0

NCC(=O)CCC(O)=O

ZGXJTSGNIOSYLO-UHFFFAOYSA-N

InChI=1S/C5H9NO3/c6-3-4(7)1-2-5(8)9/h1-3,6H2,(H,8,9)

5-amino-4-oxopentanoic acid

5-Aminolevulinic acid; Aminolevulinic acid; 106-60-5; 5-Amino-4-oxopentanoic acid; 5-Aminolevulinate; Pentanoic acid, 5-amino-4-oxo-; delta-aminolevulinic acid; Aladerm; 5451-09-2 (HCl); 106-60-5 (free); 868074-65-1 (phosphate)

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

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 (~762.60 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (19.07 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 25.0 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 2: ≥ 2.5 mg/mL (19.07 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 3: ≥ 2.5 mg/mL (19.07 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 25.0 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.)