Alzheimer’s disease (AD) is an age-related neurodegenerative disease that is mediated by multiple signaling pathways. In recent years, the components of Psoralea Fructus (PF) have demonstrated some anti-Alzheimer effects both in vitro and in vivo. To further reveal the active compounds of PF and their mechanisms regulating key targets of AD, in this study, we identified four prenylated compounds from the 70% ethanolic aqueous extract of PF, namely bavachin, bavachinin, bavachalcone, and isobavachalcone. Multi-target bioactivity analysis showed that these compounds could differentially inhibit neuroinflammation, oxidative damage, and key AD-related protein targets, such as amyloid β-peptide 42, β-secretase, glycogen synthase kinase 3β, and acetylcholinesterase. These compounds may generate beneficial effects in AD prevention and treatment.
Alzheimer’s disease (AD) is a serious threat for the aging society. In this study, we examined the preventive effect of the total prenylflavonoids (TPFB) prepared from the dried fruits of Psoralea corylifolia L., using an age-related AD mouse model SAMP8. We found that long-term dietary TPFB at 50 mg/kg·day significantly improved cognitive performance of the SAMP8 mice in Morris water maze tests, similar to 150 mg/kg·day of resveratrol, a popular neuro-protective compound. Furthermore, TPFB treatment showed significant improvements in various AD markers in SAMP8 brains, which were restored to near control levels of the normal mice, SAMR1. TPFB significantly reduced the level of amyloid β-peptide 42 (Aβ42), inhibited hyperphosphorylation of the microtubule-associated protein Tau, induced phosphorylation of Ser9 of the glycogen synthase kinase 3β (GSK-3β), and decreased the expression of the proinflammatory cytokines TNFα, IL-6, and IL-1β. Finally, TPFB also markedly reduced the level of serum derivatives of reactive oxygen metabolites (d-ROMs), a biomarker of oxidative stress in vivo. These results showed that dietary TPFB could effectively prevent age-related cognitive deficits and AD-like neurobiochemical changes, and may have a potential role in the prevention of Alzheimer’s disease.
Bat coronavirus RaTG13 shares about 96.2% nucleotide sequence identity with that of SARS-CoV-2 and uses human and Rhinolophus affinis (Ra) angiotensin-converting enzyme 2 (ACE2) as entry receptors. Whether there are bat species other than R. affinis susceptible to RaTG13 infection remains elusive. Here, we show that, among 18 different bat ACE2s tested, only RaACE2 is highly susceptible to transduction by RaTG13 S pseudovirions, indicating that the bat species harboring RaTG13 might be very limited. RaACE2 has seven polymorphic variants, RA-01 to RA-07, and they show different susceptibilities to RaTG13 S pseudovirions transduction. Sequence and mutagenesis analyses reveal that residues 34, 38, and 83 in RaACE2 might play critical roles in interaction with the RaTG13 S protein. Of note, RaACE2 polymorphisms have minimal effect on S proteins of SARS-CoV-2 and several SARS-CoV-2 related CoVs (SC2r-CoVs) including BANAL-20-52 and BANAL-20-236 in terms of binding, membrane fusion, and pseudovirus entry. Further mutagenesis analyses identify residues 501 and 505 in S proteins critical for the recognition of different RaACE2 variants and pangolin ACE2 (pACE2), indicating that RaTG13 might have not been well adapted to R. affinis bats. While single D501N and H505Y changes in RaTG13 S protein significantly enhance the infectivity and minimize the difference in susceptibility among different RaACE2 variants, an N501D substitution in SARS-CoV-2 S protein displays marked disparity in transduction efficiencies among RaACE2 variants with a significant reduction in infectivity on several RaACE2 variants. Finally, a T372A substitution in RaTG13 S protein not only significantly increases infectivity on all RaACE2 variants, but also markedly enhances entry on several bat ACE2s including R. sinicus YN, R. pearsonii, and R. ferrumeiqunum. However, the T372A mutant is about 4-fold more sensitive to neutralizing sera from mice immunized with BANAL-20-52 S, suggesting that the better immune evasion ability of T372 over A372 might contribute to the natural selective advantage of T372 over A372 among bat CoVs. Together, our study aids a better understanding of coronavirus entry, vaccine design, and evolution.
Background: Dried fruits of Psoralea corylifolia L. (Psoraleae Fructus) is one of the most popular traditional Chinese medicine with treatment for nephritis, spermatorrhea, pollakiuria, asthma, and various inflammatory diseases. Bakuchiol is main meroterpenoid with bioactive diversity from Psoraleae Fructus. This study was designed to seek structural diverse bakuchiol derivants with anti-inflammatory activities from this plant. Methods: Various column chromatography methods were used for isolation experiment. Structures and configurations of these compounds were determined by spectroscopic methods and single-crystal X-ray diffraction. Their inhibition on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages were evaluated by the Griess reaction. Results: Twelve unpresented bakuchiol dimmers, bisbakuchiols M–U (1–9) and bisbakuchiol ethers A–C (10–12), along with five known compounds (13–17), were isolated from the fruits of Psoralea corylifolia L. Compounds 1–3, 10–12, 16 and 17 exhibited inhibitory activities against LPS-induced NO production in RAW264.7 macrophages, and the inhibition of compound 1 (half maximal inhibitory concentration (IC50) value = 11.47 ± 1.57 μM) was equal to that of L-N(6)-(1-iminoethyl)-lysine (IC50 = 10.29 ± 1.10 μM) as a positive control. Conclusions: Some compounds exhibited inhibitory activities against NO production, and the study of structure–activity relationship suggested that uncyclized compounds with oxygen substitution at C-12/12′ showed strong inhibitory activities, and carbonyl units contributed to enhanced activities.
Background: Fukeqianjin formula (FKQJF) is a Chinese medicine prescription, which has been widely used individually or in combination with other western medicine for the treatment of various gynecological inflammatory diseases, including chronic cervicitis, chronic pelvic inflammatory disease and endometritis, so on and so force. Methods: The ultra-fast liquid chromatography coupled with triple quadrupole tandem mass spectrometry (UFLC–MS/MS), a quick and efficient method was established and applied to quantify the major constituents of Fukeqianjin formula in rat plasma, and its pharmacokinetics of oral absorption was studied. Nineteen components in Fukeqianjin formula were detected and identified as the major compounds absorbed into the blood according to their chromatographic behavior, molecular weight, ion fragments and other information of these compounds. Furthermore, the plasma drug concentration–time curves were established and the related kinetic parameters were analyzed. Results: The results showed that all the 19 compounds could be rapidly absorbed by the gastrointestinal tract, the plasma drug concentration of most compounds could reach a peak at around 1–2 h, and the double-peaks on behalf of the enterohepatic circulation were found in most drug concentration–time curves. The method used in this experiment was validated comprehensively including specificity, linearity, precision, accuracy, stability, matrix effect, and recovery. Conclusions: These results showed that the developed method was suitable for pharmacokinetic analysis of the main components of Fukeqianjin formula in rat plasma, and may provide useful information for the subsequent distribution studies in vivo.