5-Aminolevulinic acid hydrochloride finds an important role as a precursor in the synthesis of tetrapyrroles such as chlorophyll and heme. 5-Aminolevulinic acid hydrochloride has been used to activate or inhibit heme biosynthesis in HeLa and K562 cell lines. It has also been used in photodynamic therapy for A431 tumor bearing mice.

Synthesis of 5-aminolevulinic acid hydrochloride

Take the raw material synthesized in Example 1 benzoyl glycine 5g (27.9mmol) was added to the reaction flask, and then19.55 g (195.34 mmol, 7 eq) of succinic anhydride,6.06 g (60 mmol) of triethylamine, DMAP (4 g) and pyridine 25 ml, The pyridine can react with Dakin-West under the conditions of 45 -50 for 1h,After the reaction, add 200ml of 10wt% aqueous solution of Na2CO3 and continue stirring for 30min.Cooled and alkalinized with 20 wt% sodium hydroxide solution under ice-water bath until the pH of the system was 9-10. Then, ethyl acetate was added for extraction twice (using 50 mL of ethyl acetate each time for extraction), and the corresponding Of the aqueous phase, and then add concentrated hydrochloric acid to the aqueous phase acidified to pH = 2, precipitated a large amount of solid, filtered, dried, The product benzamidyl keto acid 5.2g, yield 79.27%, purity of 99% or more.5.65 g (0.024 mol) of the benzoylaminolevulinic acid obtained above and 30 wt% hydrochloric acid (70 ml) were added and heated to reflux. After the reaction for 12h, the mixture was cooled and filtered. The filtrate was decolored with activated charcoal and then back extracted with 50ml of dichloromethane. The aqueous layer was concentrated under reduced pressure, then placed in a freezer for crystallization overnight. After filtration, the filter cake was beaten with an appropriate amount of acetone and ether and dried to give 5-aminolevulinic acid hydrochloride (3.7 g, yield 92%) as a white solid.[1]

5-Aminolevulinic acid hydrochloride loaded microbubbles

Sonodynamic therapy (SDT) is composed of sonosensitizer, low intensity ultrasound and molecular oxygen. 5-aminolevulinic acid hydrochloride (ALA) is an effective sonosensitizer for cancer treatment using SDT, ALA-mediated SDT created in vitro anti-tumour effect on pancreatic cancer cells [Citation1]. However, the ALA has the non-specific nature, so such therapies are often related to significant off-target effects. 5-Aminolevulinic acid hydrochloride (ALA)-mediated sonodynamic therapy (SDT) had anti-tumour effect on pancreatic cancer cells. Hence, ALA loaded lipid/poly(lactic-co-glycolic acid) (PLGA) microbubbles (MBs)-mediated SDT for pancreatic cancer has great potential. The average size of ALA-lipid MBs and ALA-PLGA MBs was about 3.0 μm. The two kinds of MBs had good biocompatibility to normal HPDE6-C7 cells and were not toxic to pancreatic cancer cells. Compared with 5-aminolevulinic acid hydrochloride -induced SDT, a statistically significant decrease in cell viability was observed in ALA lipid/PLGA MBs combined with ultrasound groups in AsPC-1 and BxPC-3 cells (p < .05).[2]

Microbubbles (MBs) are small gas bubbles with the diameter from 1 to 10?μm, they are stabilized by the lipid, polymer or protein shell. The MBs are safe and used as the ultrasound contrast agents, the size guarantees their passage through the lung capillaries. The MBs undergo both inertial and stable acoustic cavitations in response to ultrasound pulses. They can cause the cell membrane disruption and facilitate intracellular drug uptake at the target site. The SDT and MBs combination could significantly increase the cytotoxic effect on human breast cancer cells. We aimed to make lipid and poly(lactic-co-glycolic acid) (PLGA) MBs as the carrier of sonosensitizer 5-aminolevulinic acid hydrochloride and evaluate the effect of 5-aminolevulinic acid hydrochloride-loaded MBs on SDT in pancreatic cancer cells in vitro and in vivo.

Excessive cellular ROS formation can lead to oxidative damage to the cell components. Increased ROS played an important role for SDT-related apoptosis in cancer cells. MBs had stimulatory function on ROS production for SDT in liver cancer cells. Hyperglycaemia-induced NLRP3 inflammasome activation may be an ROS-dependent process in pyroptotic cell death. Our results showed 5-aminolevulinic acid hydrochloride mediated SDT (ALA?+?U) caused a rise in ROS generation in pancreatic cancer cells, 5-aminolevulinic acid hydrochloride -lipid/PLGA MBs mediated SDT (ALA-lipid/PLGA MBs?+?U) produced much more ROS, accompanied by the features of apoptosis and pyroptosis. In summary, we successfully developed lipid/PLGA MBs loaded the sonosensitizer 5-aminolevulinic acid hydrochloride to treat pancreatic cancer through the SDT approach. Ultrasound-induced ALA-loaded MBs destruction realized improved SDT efficacy. Our results showed a promise treatment in pancreatic cancer using the combination of ALA-loaded MBs and the locally focussed ultrasound in vitro and in vivo.

5-Aminolevulinic Acid Hydrochloride (5-ALA)–Guided Surgical Resection of High-Grade Gliomas

High-grade gliomas are a type of malignant brain tumour. Optimal management often includes maximal surgical resection. 5-aminolevulinic acid hydrochloride (5-ALA) is an imaging agent that makes a high-grade glioma fluoresce under blue light, which can help guide the surgeon when removing the tumour. We conducted a health technology assessment of 5-aminolevulinic acid hydrochloride–guided surgical resection of high-grade gliomas, which included an evaluation of effectiveness, safety, the budget impact of publicly funding 5-ALA, and patient preferences and values.[3]

5-aminolevulinic acid hydrochloride–guided surgical resection appears to improve the extent of resection of high-grade gliomas compared with surgery using standard white-light microscopy (GRADE: Low). The evidence suggests 5-ALA-guided resection may improve overall survival; however, we cannot exclude the possibility of no effect (Grade: Low). 5-aminolevulinic acid hydrochloride may improve 6-month progression-free survival, although the results are highly uncertain (GRADE: Very low). There is an uncertain impact on overall or neurological adverse events (GRADE: Very low). We did not identify any economic studies conducted from the perspective of the Ontario or Canadian public health care payer. Of the studies that met our inclusion criteria, most found 5-aminolevulinic acid hydrochloride–guided surgical resection was cost-effective compared to white-light microscopy for high-grade gliomas. However, clinical model inputs for the comparative effectiveness and safety of 5-aminolevulinic acid hydrochloride were based on limited and low-quality evidence. We estimate that publicly funding 5-ALA–guided surgical resection in Ontario over the next 5 years would result in a total 5-year budget impact of about $7,500,000. For people diagnosed with high-grade gliomas, 5-ALA is seen positively as a useful imaging tool for brain tumour resection.

Randomized Phase Study of 5-Aminolevulinic Acid Hydrochloride

Cisplatin-based chemotherapy was established in the 1980s, and it has been improved by the development of a short hydration protocol in lung cancer therapy. However, cisplatin-based chemotherapy is still associated with renal toxicity. Because 5-aminolevulinic acid hydrochloride (5-ALA) with sodium ferrous citrate (SFC) is known to be a mitochondrial activator and a heme oxygenase-1 (HO-1) inducer, 5-aminolevulinic acid hydrochloride with SFC is speculated to mitigate cisplatin-induced renal inflammation.[4]

Scientists investigated the effects of oral administration of 5-ALA with SFC for preventing cisplatin-based nephrotoxicity in patients with lung cancer and evaluated its benefits for patients who received cisplatin-based chemotherapy. The primary endpoint was the significance of the difference between the serum creatinine (sCr) levels of the patients administered 5-aminolevulinic acid hydrochloride with SFC and those given placebo after course 1 of chemotherapy. All enrolled patients completed the four cycles of cisplatin-based chemotherapy with short hydration. The average level of sCr on day 22 of course 1 was 0.707 mg/dL in the group treated with 5-ALA and SFC and 0.735 mg/dL in the placebo group, respectively, and the sCr in the test group was significantly lower than that in the placebo group (p = 0.038). In addition, the eGFR was significantly higher in the SPP-003 group than in the placebo group up to day 1 of course 3 (84.66 and 75.68 mL/min/1.73 m2, respectively, p = 0.02) and kept better even after the last administration of the study drug (82.37 and 73.49 mL/min/1.73 m2, respectively, p = 0.013). The oral administration of 5-aminolevulinic acid hydrochloride with SFC is beneficial to patients undergoing cisplatin-based chemotherapy for lung cancer with short hydration.

References

[1]TAIZHOU VOCATIONAL AND TECHNICALL COLLEGE - CN107522627, 2017, A

[2]Yang W, Xu H, Liu Q, Liu C, Hu J, Liu P, Fang T, Bai Y, Zhu J, Xie R. 5-Aminolevulinic acid hydrochloride loaded microbubbles-mediated sonodynamic therapy in pancreatic cancer cells. Artif Cells Nanomed Biotechnol. 2020 Dec;48(1):1178-1188.

[3]Ontario Health (Quality). 5-Aminolevulinic Acid Hydrochloride (5-ALA)-Guided Surgical Resection of High-Grade Gliomas: A Health Technology Assessment. Ont Health Technol Assess Ser. 2020 Mar 6;20(9):1-92.

[4]Kawamura K, Matsushima H, Sakai H, Iwashima A, Nakamura S, Kojima T, Sasaki S, Shigenaga T, Natsume I, Sasaki T, Ohsaki Y, Iwanaga K, Nishi K, Mitsuishi Y, Taniguchi H, Sato K, Yamauchi M, Nakajima M, Takahashi K. A Randomized Phase 2 Study of 5-Aminolevulinic Acid Hydrochloride and Sodium Ferrous Citrate for the Prevention of Nephrotoxicity Induced by Cisplatin-Based Chemotherapy of Lung Cancer. Oncology. 2022;100(11):620-632.