Isosafrole

Isosafrole, a stiripentol analog, is a potent LDH inhibitor. Stiripentol is a new-generation antiepileptic drug, and its chemical structure is unrelated to other antiepileptic drugs. Seizures and epileptiform activity are reduced by inhibition of the metabolic pathway via lactate dehydrogenase (LDH), which is a component of the astrocyte-neuron lactate shuttle.
Isosafrole is a substructure of stiripentol that lacks the hydroxyl group and tertiary-butyl group of stiripentol. Isosafrole strongly inhibited the pyruvate-to-lactate conversion by both LDH1 and LDH5, suggesting that it inhibits lactate production itself. Isosafrole (200 to 300 mg/kg ip) strongly suppressed spontaneous high-voltage spikes and paroxysmal discharges in the kainate model in vivo.  Isosafrole suppresses seizures in vivo. Going by the lactate reduction by ketogenic diets, LDH inhibitors for the pyruvate-to-lactate conversion, such as isosafrole, would be more effective for antiepileptic actions.
References:
[1]. Sada N, Lee S2, Katsu T et al. Epilepsy treatment. Targeting LDH enzymes with a stiripentol analog to treat epilepsy. Science. 2015 Mar 20;347(6228):1362-7.

Inducibility of hepatic CYP1A enzymes by 3-methylcholanthrene and isosafrole differs in male rats fed diets containing casein, soy protein isolate or whey from conception to adulthood.[Pubmed:11285323]

J Nutr. 2001 Apr;131(4):1180-8.

Hepatic cytochrome P450 (CYP)1A1 and 1A2 enzymes were studied in male Sprague-Dawley rats derived from 5-7 litters fed diets in which the protein source was casein, soy protein isolate or whey. At age 65 d, rats were gavaged with corn oil (vehicle), 40 mg/kg 3-methylcholanthrene (3-MC) or 75 mg/kg Isosafrole (ISO). Hepatic expression of CYP1A1 and CYP1A2 mRNA, apoprotein and associated monooxygenase activities were measured 17 h later. No significant dietary effects were observed on basal expression of either enzyme. However, interactions between diet and the two inducers (3-MC and ISO) were observed in soy-fed rats for ethoxy- and methoxyresorufin O-dealkylase activity, CYP1A1 and CYP1A2 apoprotein and mRNA (P < 0.05). The level of induction of CYP1A1 mRNA and apoprotein was lower in rats fed soy diets than in rats fed casein diets (P < 0.05), and the level of induced CYP1A2 mRNA was lower in rats fed soy or whey (P < 0.05) after treatment with the aryl hydrocarbon (Ah) receptor-dependent inducer 3-MC. This was accompanied by a 50% reduction in constitutive levels of the Ah receptor in liver cytosol of soy-fed, relative to casein-fed rats, and a slightly smaller reduction in whey-fed rats. Expression of the Ah receptor correlated with 3-MC-inducibility of CYP1A1 mRNA in rats fed the three diets. In contrast, in rats induced with ISO, which does not bind to the Ah receptor and induces CYP1As via different mechanisms than 3-MC, ethoxyresorufin O-deethylase activity and levels of CYP1A1 apoprotein and mRNA were elevated to a greater degree in soy-fed than in casein- or whey-fed rats (P < 0.05). Moreover, after ISO treatment, induction of methoxyresorufin O-demethylase activity, CYP1A2 apoprotein and mRNA levels was observed only in rats fed soy (P < 0.05). These data suggest potential effects of dietary protein source on metabolism of a wide variety of CYP1A substrates, including environmental and dietary carcinogens, many of which induce their own metabolism.

Chemical markers from the peracid oxidation of isosafrole.[Pubmed:18508215]

Forensic Sci Int. 2008 Jul 18;179(1):44-53.

In this work, isomers of 2,4-dimethyl-3,5-bis(3,4-methylenedioxyphenyl)tetrahydrofuran (11) are presented as chemical markers formed during the peracid oxidation of Isosafrole. The stereochemical configurations of the major and next most abundant diastereoisomer are presented. Also described is the detection of isomers of (11) in samples from a clandestine laboratory uncovered in South Australia in February 2004.

Microbiologic oxidation of isosafrole into piperonal.[Pubmed:12721444]

Appl Biochem Biotechnol. 2003 Spring;105 -108:649-57.

The biotransformation of Isosafrole by Cladosporium sphaerospermum yielded piperonal, which is a compound of great commercial importance in the flavor and fragrance industries. The experiments were performed in 500-mL conical flasks containing 100 mL of Czapek-modified medium in an orbital shaker with controlled agitation and temperature. Spores of C. sphaerospermum were used as inocula, and after 96 h of incubation the substrate was added to the culture. Samples of 2 mL were withdrawn at 24-h intervals and analyzed by gas chromatography, (GC) and/or GC/MS spectroscopy.

Catalytic and immunochemical properties of hepatic cytochrome P450 1A in three avian species treated with beta-naphthoflavone or isosafrole.[Pubmed:11544144]

Comp Biochem Physiol C Toxicol Pharmacol. 2001 Sep;130(1):67-83.

Induction of cytochrome P450 1A (CYP1A) can be used as a biomarker of exposure to planar halogenated aromatic hydrocarbons (PHAHs). Our objective was to characterize the induction of CYP1A activity and protein in three avian species following in vivo treatment with beta-naphthoflavone (BNF) and/or Isosafrole. Alkoxyresorufin-O-dealkylase (alk-ROD) activities of hepatic microsomes from Herring Gulls (Larus argentatus) (HGs), Double-crested Cormorants (Phalacrocorax auritus) (DCCs) and chickens (Gallus domesticus) were measured using ethoxy-, methoxy-, pentoxy- and benzyloxy-resorufin, in the presence and absence of the inhibitors ellipticine or furafylline. Immunoreactivity of microsomal proteins with antibodies to several CYP1A proteins was investigated. CYP1A protein and alk-ROD activities of HGs and DCCs, but not chickens, were induced by Isosafrole. Ellipticine was a potent and non-selective inhibitor of alk-ROD activity in all three species, while furafylline inhibition of alk-ROD activities varied among species and treatments. In all three species, BNF induced a protein immunoreactive with monoclonal antibody to CYP1A1 from the marine fish Stenotomus chrysops (scup), but a CYP1A2-like protein was not detected in avian microsomes probed with polyclonal antibodies to mouse CYP1A2. Variations in responses among avian species indicate that CYP1A proteins and substrate specificities should be characterized for each species used in PHAH biomonitoring programs.