Discovery of nano-piperolactam A: A nonsteroidal contraceptive lead acting through down-regulation of interleukins.

Elevated serum interleukins (IL-6, IL-1ß) over baseline concentration help in blastocyst adhesion to the uterine endometrium in the early phase of pregnancy. A nano PLA (Piperolactam A)-HPBCD (2-hydroxy-propyl-ß-cyclodextrin) inclusion complex was developed as an interleukin down-regulator that exhibited 100% anti-implantation activity in rodents at a dose as low as 2.5-5.0 mg/kg. On metabolomics study, among major glyco-lipo-protein metabolites, only serum low-density lipoprotein (LDL) or very low-density lipoprotein (VLDL) levels revealed alteration by the formulation. Administration of PLA-HPBCD did not cause changes in serum estrogen and progesterone levels. However, IL-6 and IL-1ß failed to increase post PLA-HPBCD administration; hence, it is assumed to be the mode of the drug's abortifacient action. In addition, absence of signs of either acute or chronic toxicity suggests the formulation was considerably non-toxic. Therefore, the nano-PLA conjugate promises as a non-steroidal contraceptive lead apart from ormeloxifene, the only non-steroidal anti-fertility agent currently available globally.

Pharmacoinformatics study of Piperolactam A from Piper betle root as new lead for non steroidal anti fertility drug development.

Fertility control is a burning problem all over the world to regulate population overflow and maintain ecological balance. This study is an in-silico approach to explore a non-steroidal lead as contraceptive agent in order to avoid several contraindications generated by steroidal analogues. Piperolactam A, an aristolactam isolated from Piper betle Linn. showed binding affinity towards estrogen and progesterone receptor as -8.9 and -9.0Kcal/mol (inhibition constant Ki=0.294µM and 0.249µM) respectively which is even larger than that of reported antagonists such as Rohitukine and OrgC (binding affinity -8.7 and -8.4Kcal/mol; Ki 0.443µM and 0.685µM respectively). The binding site exploration displayed more hydrogen bonding of Piperolactam A (His 524, Leu 346, Thr 347) than Rohitukine and OrgC (Leu 718) with associated receptors which was further confirmed by molecular dynamics simulations. The drug-likeliness of the compound has been proved from its tally with Lipinsky's Rule of Five and lowered toxicity such as cardiac toxicity, liver toxicity, mutagenicity and ecological toxicity. Endocrine disruptome and later docking guided molecular simulations revealed that Piperolactam A has weaker binding affinity and/or lower probability of binding with nuclear receptors especially hERG and cytochrome P450. The high Caco-2 permeability suggested more bioavailability hence more therapeutic efficacy of the drug.

In Vitro susceptibilities of wild and drug resistant Leishmania donovani amastigotes to piperolactam A loaded hydroxypropyl-ß-cyclodextrin nanoparticles.

Leishmaniasis is an epidemic in various countries, and the parasite Leishmania donovani is developing resistance against available drugs. In the present study the antileishmanial action of piperolactam A (PL), isolated after bioactivity guided fractionation from root extracts of Piper betle was accentuated in detail. Activity potentiation was achieved via cyclodextrin complexation. Crude hydro-ethanolic extract (PB) and three fractions obtained from PB and fabricated PL-hydroxypropyl-ß-cyclodextrin (HPBCD) nanoparticles were evaluated for antileishmanial activity. Tests were performed against L. donovani wild-type, sodium stibogluconate, paromomycin and field isolated (GE1) resistant strains in axenic amastigote and amastigote in macrophage models. PL-HPBCD complex was characterized and FITC loaded HPBCD nanoparticles were assessed for macrophage internalization in confocal microscopic studies. Isolated and purified PL from most potent, alkaloid rich ethyl acetate fraction of PB showed high level of antileishmanial activities in wild-type (IC50=36 µM), sodium stibogluconate resistant (IC50=103 µM), paromomycin resistant (IC50=91 µM) and field isolated resistant (IC50=72 µM) strains together with cytotoxicity (CC50=900 µM) in mouse peritoneal macrophage cells. Inclusion of PL in HPBCD nanoparticles resulted in 10-fold and 4-10-fold increase in selectivity indexes (CC50/IC50) for wild-type and drug resistant strains, respectively. Drug-carrier interactions were clearly visualized in FT-IR studies. Complete incorporation of PL in HPBCD cavity was ascertained in DSC and XRD analyses. 180nm size stable nanospheres showed macrophage internalization within 1h of incubation. Piperolactam A (PL), a representative of the inchoate skeleton of aristolactam chassis might be the source of safe and affordable antileishmanial agents for the cure of deadly Leishmania infections.

Phenolic aristolactams from leaves and stems of Aristolochia chilensis / Aristolactamas fenólicas de hojas y tallos de Aristolochia chilensis

Three phenolic aristolactams, aristolactam AII (3), velutinam (4) and piperolactam A (5), were identified from the leaves and stems of Aristolochia chilensis Bridges ex Lindl. The structures of these compounds were elucidated using a combination of HPLC-DAD, GC-MS and NMR experiments.

Tres aristolactamas fenólicas aristolactama AII(3), velutinam(4) y piperolactama A(5), se identificaron en hojas y tallos de Aristolochia chilensis Bridges ex Lindl. Las estructuras de estos compuestos se determinaron por combinación de CLAE-DAD, CG-EM y experimentos de RMN.