Two new triterpenoids from the leaves of Cyclocarya paliurus (Batalin) Iljinskaja.

Two previously undescribed triterpenoids (1-2), along with thirteen known compounds (3-15) were isolated from a CHCl3-soluble extract of the leaves of Cyclocarya paliurus. Their structures were established on the basis of chemical and spectroscopic approaches. These compounds were assessed for their therapeutic effects on diabetic nephropathy (DN)-evoked fibrosis through High-Glucose and transforming growth factor-ß1 (TGF-ß1) challenged HK-2 cells. Among them, compounds 3, 5 and 8 could remarkedly decrease the level of fibronectin to relieve DN with 27.66 ± 2.77%, 6.09 ± 0.57% and 17.74 ± 5.83% inhibition rate at 10 µM, 10 µM and 1 µM, respectively.

Four new dammarane triterpenoid glycosides from the leaves of Cyclocarya paliurus and their SIRT1 activation activities.

Four new C-11 monosaccharide attached dammarane triterpenoid glycosides cypaliurusides SV (1-4), along with nine known dammarane triterpenoid glycosides (5-13) were isolated from a CHCl3-soluble extract of the leaves of Cyclocarya paliurus. All characterized compounds were assayed for their cytotoxicities against HepG2 cells and 10 compounds were evaluated for the agonistic effects on sirtuin1 (SIRT1). The results showed that compounds 1, 5 and 6 were strongly cytotoxic in HepG2 cell line. Two dammarane triterpenoid glycosides 3 and 10 exhibited agonistic activities on SIRT1 with IC50 of 10 µM and 20 µM, respectively.

Adaptation of the FK506 binding protein 1B to hibernation in bats.

Hibernation is an adaptive strategy used by some animals to cope with cold and food shortage. The heart rate, overall energy need, body temperature, and many other physiological functions are greatly reduced during torpor but promptly return to normal levels upon arousal. The heartbeat of torpid bats can be hundreds fold lower than that of active bats, indicating that hibernating bats have a remarkable ability to control excitation-contraction coupling in cardiac muscle. FKBP1B (calstabin 2), a peptidyl-prolyl cis-trans isomerase, is critical for the regulation of excitation-contraction coupling. Whether FKBP1B is adapted to hibernation in bats is not known. Evolutionary analyses showed that the ω values of the Fkbp1b genes of 25 mammalian species are all less than 1, and amino acid sequence alignments revealed that FKBP1B proteins are highly conserved in mammals. The expression of the Fkbp1b gene was found to be elevated at both mRNA and protein levels in two distantly related bats (Rhinolophus ferrumequinum in Yinpterochiroptera and Myotis ricketti in Yangochiroptera) during torpor. Transcription factors such as YY1 and SPs were bioinformatically determined to have a higher binding affinity to the potential regulatory regions of Fkbp1b genes in hibernating than in non-hibernating mammals. This study provides new insights into the molecular evolution of Fkbp1b in adaptation to bat hibernation.