Ca2+ releasing effect of perezone on adrenal cortex mitochondria

Perezone and its phenyl glycine derivative induce cytotoxicity via caspases on human glial cancer cells

The new phenyl glycine derivative of perezone was obtained in a single reaction step in ca. 80% yield which showed remarkable cytotoxic activity against the astrocytoma U-251 cell line. After 24 h of exposure, both perezone (IC50 = 6.83 ± 1.64 µM) and its phenyl glycine derivative (2.60 ± 1.69 µM) showed cytotoxic effect on U-251 cells but were five times less cytotoxic on the non-tumoral SVGp12 cell line (IC50 = 28.54 ± 1.59 and 31.87 ± 1.54 µM respectively). Both compounds induced cellular morphological changes (pyknosis or cytoplasmic vacuolization) and increased the expression of caspases 3, 8, and 9 genes related to apoptosis. In the acute toxicity study, phenyl glycine perezone (DL50 = 2000 mg/Kg) demonstrated to be less toxic than perezone (DL50 = 500 mg/Kg). Phenylglycine-perezone can envisage a beneficial therapeutic potential.

A Timeline of Perezone, the First Isolated Secondary Metabolite in the New World, Covering the Period from 1852 to 2020

This chapter covers a sesquiterpene quinone, commonly named perezone. This molecule is documented as the first secondary metabolite isolated in crystalline form in the New World in 1852. An introduction, with its structure, the IUPAC nomenclature, and the most recent physical and spectroscopic characterizations are firstly described initially. Alongside this, a timeline and scheme with summarized information of the history of this molecule is given including the "Códice Badiano de la Cruz, 1552, highlighting the year of its isolation culminating with information up to 2005. Subsequently, in a chronological order the most recent advances of the target molecule are included and organized in subsections covering the last 15-year period 2006-2020. Finally, recently submitted contributions from the laboratory of the authors are described. It is important to note that the details provided highlight the importance and relevance of perezone.

Perezone and its isomer isoperezone induce caspase-dependent and caspase-independent cell death

In this study, we investigated the cytotoxic effect of perezone, a constituent isolated from the roots of Perezia spp. and of its synthetic isomer isoperezone on the K562 human leukemia cell line. Perezone showed greater cytotoxic effect than isoperezone but both compounds were found to induce cytotoxicity trough a caspase-dependent and a caspase-independent mechanisms; important changes in their light scattering properties, phosphatidylserine translocation and mitochondrial membrane potential disruption were detected by cytometry. The mechanism of death induction of each compound showed interesting concentration-dependent differences. Neither compound induced the apoptosis inducing factor.

Identification of compounds selectively killing multidrug-resistant cancer cells

There is a great need for the development of novel chemotherapeutic agents that overcome the emergence of multidrug resistance (MDR) in cancer. We catalogued the National Cancer Institute's DTP drug repository in search of compounds showing increased toxicity in MDR cells. By comparing the sensitivity of parental cell lines with MDR derivatives, we identified 22 compounds possessing MDR-selective activity. Analysis of structural congeners led to the identification of 15 additional drugs showing increased toxicity in Pgp-expressing cells. Analysis of MDR-selective compounds led to the formulation of structure activity relationships and pharmacophore models. This data mining coupled with experimental data points to a possible mechanism of action linked to metal chelation. Taken together, the discovery of the MDR-selective compound set shows the robustness of the developing field of MDR-targeting therapy as a new strategy for resolving Pgp-mediated MDR.

Antifeedant and phytotoxic activity of the sesquiterpene p-benzoquinone perezone and some of its derivatives

The sesquiterpene p-benzoquinone perezone (1), isolated from Perezia adnata var. alamani (Asteraceae), and its non-natural derivatives isoperezone (2), dihydroperezone (3), dihydroisoperezone (4), and anilidoperezone (5) were tested as antifeedants against the herbivorous insects Spodoptera littoralis, Leptinotarsa decemlineata, and Myzus persicae. Compounds 1-5 exhibited strong antifeedant activity against L. decemlineata and M. persicae, and elicited a low response by S. littoralis. Antifeedant activity on L. decemlineata and M. persicae increased when the hydroxyl group at C-3 in perezone (1) was changed to C-6 to give isoperezone (2). The same effect was found with hydrogenation of the double bond of the alkyl chain of (1) to yield dihydroperezone (3). In contrast, hydrogenation of this double bond in isoperezone (2) to give dihydroisoperezone (4) led to a reduction in antifeedant activity. Determination of the phytotoxic activity of 1-5 revealed that 3 had a significant inhibition effect on Lactuca sativa radicle length growth.

Myocardial protective effect of octylguanidine against the damage induced by ischemia reperfusion in rat heart

This study shows that the hydrophobic cation octylguanidine protects against myocardial damage induced by ischemia-reperfusion. The protective effect of the amine was analyzed after 5 min of coronary occlusion followed by 5 min reperfusion in rat hearts. ECG tracings from rats treated with an i.v., injection of 5 mg/kg of octylguanidine showed a total absence of post-reperfusion arrhythmias, conversely to what was observed in untreated rats. The histological images showed that myocardium fibers from treated rats were in good shape and retained their striae, also there was absence of edema. Furthermore, the accumulation of 201Tl in hearts from these rats indicated that the tissue did not suffer disruption or impairment in membrane functions. The above correlated with the fact that mitochondria isolated from the ventricular free wall from treated rats preserved their ability to synthesize ATP. We propose that the protective effect of octylguanidine might be due to its documented inhibitory action on the opening of mitochondrial non-specific pores, a mechanism which is associated in heart injury as induced by reperfusion.

Effect of perezone on arrhythmias and markers of cell injury during reperfusion in the anesthetized rat

In the in vivo rat heart model with transient (5 min) regional ischemia, as induced by left coronary artery ligation, we have demonstrated that perezone reduces dramatically the incidence of reperfusion-induced-arrhythmias. Administered 5 minutes before coronary occlusion, at a dose of 3.1 mg/kg, this drug effectively protects against the high incidence of arrhythmias and the fall of blood pressure. In addition, it inhibits the release of lactic dehydrogenase and creatine-kinase enzymes to the plasma. We propose that the protective effect of perezone might be related to its well documented action of promoting the release of intramitochondrial Ca2+, thus, maintaining ATP production during reperfusion.

Actions of perezone on rat smooth muscle

1. Perezone (PZN) on the in vitro intestinal smooth muscle of the rat relaxes the basal tonus of the smooth muscle, interrupts spontaneous activity and also blocks the contractile response induced by ACh, K+, and Ba2+; these actions are dose dependent. 2. Although in presence of small doses of PZN, the isometric contractile response to ACh was increased. 3. In calcium free intestinal smooth muscle preparation, the addition of PZN in low dose before Ca2+ increased the contractile effect of added calcium to the bath, but in presence of high doses of PZN the response to calcium was depressed. 4. PZN in calcium free preparations antagonized the contraction caused by adding barium. 5. These findings suggested that with small doses of PZN more availability of intracellular calcium free exist and/or an increase in excitability and/or an inhibition of AChase could coexist. 6. The responses of the intestine to high doses of PZN were possibly in part by blocking calcium entry. 7. The smooth muscle responses to PZN suggest that it has a membranal effect and/or an action on the internal calcium stores possibly increasing the intracellular calcium concentration. It is likely to be the expression of an increase in the intracellular calcium concentration above the levels normally reached that would be responsible for uncoupling of the smooth muscle, which would occur if the [Ca2+]i rises excessively.