Neuroprotection of total steroid saponins from Dioscorea zingiberensis C.H.Wright against transient focal cerebral ischemia-reperfusion injury in rats via its anti-inflammatory and anti-apoptotic effects

OBJECTIVE The total steroid saponins(TSSN)isolated from Dioscorea zingiberensis C.H.Wright(D.zingiberensis)has shown a variety of beneficial bioactivities.However,there are no reports about the neuroprotective effects of the TSSN until now.Therefore,we explored the neuroprotective effects of TSSN on rats against transient focal cerebral ischemia-reperfusion(I/R)and the underlying mechanisms.METHODS The healthy adult Sprague-Dawley rats were randomly assigned into six groups.After pre-treatment with the TSSN intragastrically for six days,the rats were subjected to the ischemia injury by the surgery of middle cerebral artery occlusion(MCAO)for 90 min.Some indexes were evaluated and detected.RESULTS As compared to the I/R group,TSSN group of rats,especially given the 30 mg·kg^-1 of TSSN,not only marked reduction in the neurological deficit scores,cerebral infarct volume,and brain edema,but also an increase in neuron survival(Nissl bodies)in the hippocampal cornuammons 1(CA1)and cortex hemisphere of the ipsilateral ischemia.At the same time,the inflammatory cytokines in serum induced by MCAO were significantly alleviated by the TSSN pre-administration.What′s more,the increase of caspase-3 was evidently reduced in the CA1 and cortex of the hemisphere injured brain.Finally,the down-regulating anti-apoptotic Bcl-2 and up-regulating pro-apoptotic Bax proteins were obviously suppressed.CONCLUSION TSSN plays a potential neuroprotective role against a severe injury induced by transient focal cerebral ischemic reperfusion in a rat experimental model,and this role may be mediated by its antiinflammatory and anti-apoptotic actions.

A near-infrared fluorescent probe for visualizing transformation pathway of Cys/Hcy and H2S and its applications in living system

Sulfydryl-contained(-SH)substances including hydrogen sulfide(H_(2)S),cysteine(Cys),homocysteine(Hcy)and glutathione(GSH)play crucial roles in living systems,and their variations are closely associated with various diseases.Herein,we developed a near-infrared intramolecular charge transfer(ICT)based fluorescent probe Y-NBD,achieving detection of Cys/Hcy and H_(2)S with different fluorescent signals(green-red for Cys/Hcy,red for H_(2)S),large Stokes shifts(∼100/105nm or 191 nm)and high signal-background-ratio,but not responding to GSH.Y-NBD was successfully applied to image exogenous/endogenous Cys/Hcy and H_(2)S in various living cancer cells(HeLa,A549,and HepG2)and in zebrafish.It not only visualized the transformation pathway of several thiols in HepG2 cells but also verified that the intestine is the main site for the activation and metabolism of Y-NBD in zebrafish,as well as realized to evaluate the degree of drug-induced liver injury.This work provides a promising tool for imaging Cys/Hcy and H_(2)S in living systems and shows great potency in evaluating drug-induced liver injury and its treatment.

HPLC Fingerprint and LC-TOF-MS Analysis on Extract from Roots of Gentiana macrophylla

Objective Establishing a fingerprint method to identify the characteristic chemicals in the roots of Gentiana macrophylla and evaluate their quality. Methods RP-HPLC was developed for fingerprint analysis and determination of four ingredients in G. macrophylla roots from different sources. LC-ESI-TOF-MS was employed to identify the chromatographic peaks of the fingerprint. Results Five common peaks were identified by comparing their retention time with reference secoiridoid glucosides. Eight major peaks in chromatographic fingerprint were analyzed by on-line LC-ESI-TOF-MS. Four secoiridoid glucosides were identified based on their MS data. Conclusion The method is specific and could be served for the quality identification and comprehensive evaluation of G. macrophylla.

Regioselective synthesis and initial evaluation of a folate receptor targeted rhaponticin prodrug

改进 rhaponticin (RHA ) 的治疗学的效果，叶酸的受体(FR ) 指向了 RHA prodrug 被利用经由一个能释放的二硫化物连接器连接到 folic 酸(FA ) 的一个吸水的肽分隔符设计并且 regioselectively 综合了。一系列生物评估在 vitro 并且在 vivo 被调查。生物调查的积极结果在指向的这篇小说前保证进一步现出症状之前的潜的学习化学疗法为临床的调查被考虑。

A visible-light-photocatalytic water-splitting strategy for sustainable hydrogenation/deuteration of aryl chlorides

Hydrogenation/deuteration of carbon chloride(C–Cl)bonds is of high significance but remains a remarkable challenge in synthetic chemistry,especially using safe and inexpensive hydrogen donors.In this article,a visible-light-photocatalytic watersplitting hydrogenation technology(WSHT)is proposed to in-situ generate active H-species(i.e.,Had)for controllable hydrogenation of aryl chlorides instead of using flammable H2.When applying heavy water-splitting systems,we could selectively install deuterium at the C–Cl position of aryl chlorides under mild conditions for the sustainable synthesis of high-valued added deuterated chemicals.Sub-micrometer Pd nanosheets(Pd NSs)decorated crystallined polymeric carbon nitrides(CPCN)is developed as the bifunctional photocatalyst,whereas Pd NSs not only serve as a cocatalyst of CPCN to generate and stabilize H(D)-species but also play a significant role in the sequential activation and hydrogenation/deuteration of C–Cl bonds.This article highlights a photocatalytic-WSHT for controllable hydrogenation/deuteration of low-cost aryl chlorides,providing a promising way for the photosynthesis of high-valued added chemicals instead of the hydrogen evolution.

A NIR fluorescent probe for imaging thiophenol in the living system and revealing thiophenol-induced oxidative stress

Thiophenol(PhSH)is an important raw material for organic synthesis,while its high toxicity to organisms makes it an environmental pollutant.Therefore,it is crucial to accurately detect PhSH and explore its metabolic process in the living system.Herein,a near-infrared(NIR)fluorescent probe TEM-FB was developed for sensing PhSH with a turn-on fluorescent signal at 719nm and a large Stokes shift(198 nm)based on generating the intramolecular charge transfer(ICT)process.TEM-FB shows high specificity and significant sensitivity towards PhSH(detection limit:10 nmol/L)via the aromatic nucleophilic substitution mechanism.Furthermore,it was successfully applied to image PhSH in multiple cell lines and in zebrafish.Notably,we revealed the oxidative stress process caused by PhSH and demonstrated that the hydrogen peroxide(H_(2)O_(2))in cells would alleviate the poisonousness from exogenous PhSH for the first time.This work provides a promising bioimaging tool for monitoring PhSH in living systems and visualizing the process of oxidative stress induced by PhSH.