Bcl-2/Bax ratio; activating Apaf-1; caspase-3

Azadirachta indica A. Juss. (Neem) is an Indian tree recognized for its activity as pesticide, as well as several pharmacological properties. Among the various compounds already isolated and studied from Neem tree, azadirachtin (AZA) was identified as the main bioactive compound. Azadirachtin can be found at different parts of the Neem plant but assumes its maximum concentration at the seed level. This compound features a quite complex chemical structure, which justifies the 20-plus-year difficulty to identify the synthetic pathway that subsequently permitted to carry out its artificial synthesis. Azadirachtin is widely used as a basis for production of biopesticides; nevertheless, other properties have been recognized for this substance, among which the anticancer and antimalarial activity stand out. The methods available for azadirachtin extraction are diverse, including solid-liquid extraction and extraction with solvents at high or low temperatures. Alcohol based solvents are associated with higher extraction yields and are therefore preferred for the isolation of azadirachtin from plant parts. Clean-up of the extracts is generally required for further purification. The highest azadirachtin levels have been obtained from Neem seeds but concentration values present a large variation between batches. Therefore, in addition to extraction procedures, it is essential to establish routine methods for azadirachtin identification and quantification. Chromatography-based techniques are preferably selected for detection and quantification of azadirachtin in plant matrices. Overall, this process will guarantee a future reproducible, safe and effective use of the extracts in formulations for commercial applications.[1]

The neem tree has attracted considerable research attention as a rich source of limonoids that have potent antioxidant and anti-cancer properties. The present study was designed to evaluate the chemopreventive potential of the neem limonoids azadirachtin and nimbolide based on in vitro antioxidant assays and in vivo inhibitory effects on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis. Both azadirachtin and nimbolide exhibited concentration-dependent anti-radical scavenging activity and reductive potential in the order: nimbolide > azadirachtin > ascorbate. Administration of both azadirachtin and nimbolide inhibited the development of DMBA-induced HBP carcinomas by influencing multiple mechanisms including prevention of procarcinogen activation and oxidative DNA damage, upregulation of antioxidant and carcinogen detoxification enzymes and inhibition of tumour invasion and angiogenesis. On a comparative basis, nimbolide was found to be a more potent antioxidant and chemopreventive agent and offers promise as a candidate agent in multitargeted prevention and treatment of cancer.[3]

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Considering the role of retinoids in regulation of more than 500 genes involved in cell cycle and growth arrest, a detailed understanding of the mechanism and its regulation is useful for therapy. The extract of the medicinal plant Neem (Azadirachta indica) is used against several ailments especially for anti-inflammatory, anti-itching, spermicidal, anticancer, and insecticidal activities. In this report we prove the detailed mechanism on the regulation of retinoic acid-mediated cell signaling by azadirachtin, active components of neem extract. Azadirachtin repressed all trans-retinoic acid (ATRA)-mediated nuclear transcription factor κB (NF-κB) activation, not the DNA binding but the NF-κB-dependent gene expression. It did not inhibit IκBα degradation, IκBα kinase activity, or p65 phosphorylation and its nuclear translocation but inhibited NF-κB-dependent reporter gene expression. Azadirachtin inhibited TRAF6-mediated, but not TRAF2-mediated NF-κB activation. It inhibited ATRA-induced Sp1 and CREB (cAMP-response element-binding protein) DNA binding. Azadirachtin inhibited ATRA binding with retinoid receptors, which is supported by biochemical and in silico evidences. Azadirachtin showed strong interaction with retinoid receptors. It suppressed ATRA-mediated removal of retinoid receptors, bound with DNA by inhibiting ATRA binding to its receptors. Overall, our data suggest that azadirachtin interacts with retinoic acid receptors and suppresses ATRA binding, inhibits falling off the receptors, and activates transcription factors like CREB, Sp1, NF-κB, etc. Thus, azadirachtin exerts anti-inflammatory and anti-metastatic responses by a novel pathway that would be beneficial for further anti-inflammatory and anti-cancer therapies.[2]

Limonoids from the neem tree (Azadirachta indica) have attracted considerable research attention in recent years owing to their potent antioxidant and anti-proliferative effects. The present study was designed to investigate the cellular and molecular mechanisms by which azadirachtin and nimbolide exert cytotoxic effects in the human cervical cancer (HeLa) cell line. Both azadirachtin and nimbolide significantly suppressed the viability of HeLa cells in a dose-dependent manner by inducing cell cycle arrest at G0/G1 phase accompanied by p53-dependent p21 accumulation and down-regulation of the cell cycle regulatory proteins cyclin B, cyclin D1 and PCNA. Characteristic changes in nuclear morphology, presence of a subdiploid peak and annexin-V staining pointed to apoptosis as the mode of cell death. Increased generation of reactive oxygen species with decline in the mitochondrial transmembrane potential and release of cytochrome c confirmed that the neem limonoids transduced the apoptotic signal via the mitochondrial pathway. Altered expression of the Bcl-2 family of proteins, inhibition of NF-kappaB activation and over-expression of caspases and survivin provide compelling evidence that azadirachtin and nimbolide induce a shift of balance toward a pro-apoptotic phenotype. Antioxidants such as azadirachtin and nimbolide that can simultaneously arrest the cell cycle and target multiple molecules involved in mitochondrial apoptosis offer immense potential as anti-cancer therapeutic drugs.[4]

Metabolism / Metabolites
Injection of a tritiated azadirachtin derivative, (22,23-(3)H)dihydroazadirachtin into locusts indicated fast clearing of radiolabeled material from the blood. Ninety percent of the applied radioactivity was excreted during the first 7 hr with the feces, whereas the remaining (22,23-(3)H)dihydroazadirachtin accumulated in the Malpighian tubules where it could be detected even 24 days after treatment. After the first 24 hr, feces contained at least three polar, unidentified metabolites but no (22,23-(3)H)dihydroazadirachtin.

[1]. Fernandes SR, et al. Chemistry, bioactivities, extraction and analysis of azadirachtin: State-of-the-art. Fitoterapia. 2019 Apr;134:141-150.
[2]. Thoh M, et al. Azadirachtin interacts with retinoic acid receptors and inhibits retinoic acid-mediated biological responses. J Biol Chem. 2011 Feb 11;286(6):4690-702. doi: 10.1074/jbc.M110.169334. Epub 2010 Dec 2. Retraction in: J Biol Chem. 2013 Mar 22;288(12):8563.
[3]. Priyadarsini RV, et al. The neem limonoids azadirachtin and nimbolide inhibit hamster cheek pouch carcinogenesis by modulating xenobiotic-metabolizing enzymes, DNA damage, antioxidants, invasion and angiogenesis. Free Radic Res. 2009 May;43(5):492-504.
[4]. Priyadarsini RV, et al. The neem limonoids azadirachtin and nimbolide induce cell cycle arrest and mitochondria-mediated apoptosis in human cervical cancer (HeLa) cells.

Azadirachtin A is a member of the family of azadirachtins that is isolated from the neem tree (Azadirachta indica). It has a role as a hepatoprotective agent. It is an azadirachtin, an organic heterotetracyclic compound, an acetate ester, an epoxide, an enoate ester, a cyclic hemiketal, a tertiary alcohol, a secondary alcohol and a methyl ester.
Azadirachtin has been reported in Azadirachta indica and Azadirachta with data available.

C35H44O16

720.7143

720.262

C, 58.33; H, 6.15; O, 35.52

11141-17-6

5281303

Microcrystalline powder
Yellow green powder

1.5±0.1 g/cm3

792.4±60.0 °C at 760 mmHg

159ºC

244.8±26.4 °C

0.0±6.3 mmHg at 25°C

1.623

1.75

3

16

10

51

1660

16

O1[C@@]2(C([H])([H])[H])[C@]3([H])[C@]4(C([H])=C([H])O[C@@]4([H])OC([H])(C3([H])[H])[C@@]12[C@]1(C([H])([H])[H])[C@@]([H])(C2([H])[C@@]3([H])[C@](C(=O)OC([H])([H])[H])(C([H])([H])O2)[C@@]([H])(C([H])([H])[C@@]([H])([C@]23C([H])([H])O[C@](C(=O)OC([H])([H])[H])([C@@]12[H])O[H])OC(/C(=C(\[H])/C([H])([H])[H])/C([H])([H])[H])=O)OC(C([H])([H])[H])=O)O[H])O[H]

FTNJWQUOZFUQQJ-NDAWSKJSSA-N

InChI=1S/C35H44O16/c1-8-15(2)24(38)49-18-12-19(48-16(3)36)32(26(39)43-6)13-46-21-22(32)31(18)14-47-34(42,27(40)44-7)25(31)29(4,23(21)37)35-20-11-17(30(35,5)51-35)33(41)9-10-45-28(33)50-20/h8-10,17-23,25,28,37,41-42H,11-14H2,1-7H3/b15-8+/t17-,18+,19-,20+,21-,22-,23-,25+,28+,29-,30+,31+,32+,33+,34+,35+/m1/s1

dimethyl (1S,4S,5R,6S,7S,8R,11S,12R,14S,15R)-12-acetyloxy-4,7-dihydroxy-6-[(1S,2S,6S,8S,9R,11S)-2-hydroxy-11-methyl-5,7,10-trioxatetracyclo[6.3.1.02,6.09,11]dodec-3-en-9-yl]-6-methyl-14-[(E)-2-methylbut-2-enoyl]oxy-3,9-dioxatetracyclo[6.6.1.01,5.011,15]pentadecane-4,11-dicarboxylate

azadirachtin; Azadirachtin A; 11141-17-6; Nimbicidine; NeemAzal; Nimurin; Ornazin; Azatin;

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: This product requires protection from light (avoid light exposure) during transportation and storage.

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 (~138.75 mM)

Solubility in Formulation 1: ≥ 2.5 mg/mL (3.47 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 (3.47 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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 (Please use freshly prepared in vivo formulations for optimal results.)