Exosomes derived from human umbilical cord mesenchymal stem cells alleviate Parkinson’s disease and neuronal damage through inhibition of microglia

Microglia-mediated inflammatory responses have been shown to play a crucial role in Parkinson’s disease. In addition, exosomes derived from mesenchymal stem cells have shown anti-inflammatory effects in the treatment of a variety of diseases. However, whether they can protect neurons in Parkinson’s disease by inhibiting microglia-mediated inflammatory responses is not yet known. In this study, exosomes were isolated from human umbilical cord mesenchymal stem cells and injected into a 6-hydroxydopamine-induced rat model of Parkinson’s disease. We found that the exosomes injected through the tail vein and lateral ventricle were absorbed by dopaminergic neurons and microglia on the affected side of the brain, where they repaired nigral-striatal dopamine system damage and inhibited microglial activation. Furthermore, in an in vitro cell model, pretreating lipopolysaccharide-stimulated BV2 cells with exosomes reduced interleukin-1β and interleukin-18 secretion, prevented the adoption of pyroptosis-associated morphology by BV2 cells, and increased the survival rate of SH-SY5Y cells. Potential targets for treatment with human umbilical cord mesenchymal stem cells and exosomes were further identified by high-throughput microRNA sequencing and protein spectrum sequencing. Our findings suggest that human umbilical cord mesenchymal stem cells and exosomes are a potential treatment for Parkinson’s disease, and that their neuroprotective effects may be mediated by inhibition of excessive microglial proliferation.

Efficacy of immunosuppression monotherapy after liver transplantation:A meta-analysis

AIM:To assess the advantages and disadvantages of immunosuppression monotherapy after transplantation and the impact of monotherapy on hepatitis C virus(HCV)recurrence.METHODS:Articles from Cochrane Hepato-Biliary Group Controlled Trials Register,the Cochrane Central Register of Controlled Trials in The Cochrane Library,MEDLINE,EMBASE,and Science Citation Index Expanded,including non-English literature identified in these databases,were searched up to January 2013.We included randomized clinical trials comparing various immunosuppression monotherapy and prednisone-based immunosuppression combinations for liver transplantation.The modified Jadad scale score or the Oxford quality scoring system was used.Meta-analyses were performed with weighted random-effects models.RESULTS:A total of 14 randomized articles including 1814 patients were identified.Eight trials including1214 patients compared tacrolimus monotherapy(n=610)vs tacrolimus plus steroids or triple therapy regarding acute rejection and adverse events(n=604).Five trials,including 285 patients,compared tacrolimus monotherapy(n=143)vs tacrolimus plus steroids or triple therapy regarding hepatitis C recurrence(n=142).Four trials including 273 patients compared cyclosporine monotherapy(n=148)vs cyclosporine and steroids regarding acute rejection and adverse events(n=125).Two trials including 170 patients compared mycophenolate mofetil monotherapy(n=86)vs combinations regarding acute rejection(n=84).There were no significant differences in the acute rejection rates between tacrolimus monotherapy(RR=1.04,P=0.620),and cyclosporine monotherapy(RR=0.89,P=0.770).Mycophenolate mofetil monotherapy had a significant increase in the acute rejection rate(RR=4.50,P=0.027).Tacrolimus monotherapy had no significant effects on the recurrence of hepatitis C(RR=1.03,P=0.752).More cytomegalovirus infection(RR=0.48,P=0.000)and drug-related diabetes mellitus(RR=0.54,P=0.000)were observed in the immunosuppression combination therapy groups.CONCLUSION:Tacrolimus and cyclosporine monotherapy may be as effective as immunosuppression combination therapy.Mycophenolate mofetil monotherapy was not considerable.Tacrolimus monotherapy does not increase recurrence of HCV.

Pressure-induced bimetallic carbon nanotubes from metalorganic frameworks as optimized bifunctional electrocatalysts for water splitting

Carbon nanotubes(CNTs)have attracted great interest in numerous applications due to their excellent electronic and structural properties.However,harsh synthesis conditions and high energy consumption limit the further application of CNTs.Herein,we developed a facile and innovative strategy to generate CNTs by physically pressurizing metal-organic frameworks(MOFs)and then pyrolyzing.The synthesized bimetallic nitrogen/sulfur double-doped carbon nanotubes are denoted as Fe_(x)Co_(1-x)P(x=0.5,0.6,0.7,0.8,0.9).The introduction of pressure not only revolutionized the morphology of the electrocatalysts,but also enhanced the activity of oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)in alkaline solution.Fe_(0.6)Co_(0.4)-P exhibits superior OER and HER performances in 1.0 mol·L^(-1)KOH solution with overpotentials of 364 and 346 mV at 10 mA·cm^(-2),which are 28 and 5 mV lower than unpressurized Fe0.6Co0.4.

Construction of dual crosslinked network binder via sequential ionic crosslinking for high-performance silicon anodes

Nowadays,silicon has become a promising anode active material for lithium-ion batteries due to its high specific capacity.However,traditional binder materials cannot effectively restrain the volume expansion of silicon during lithiation/delithiation.Inspired by the growth process of climbing plants,we sequentially crosslink sodium alginate with calcium ions and hyperbranched polyethyleneimine to construct a dual crosslinked network binder.During the sequentially crosslinking,sodium alginate preferentially crosslinks with Ca^(2+)to form the"trellis"network,which restricts the free movement of hyperbranched polyethyleneimine and guides it,like"vine",to gradually anchor on the surrounding"trellis"through hydrogen and ionic bonding.In this dual crosslinked network,the ionic ally crosslinked sodium alginate maintains the anode structural integrity;the anchored hyperbranched polyethyleneimine forms strong multidimensional hydrogen bonds with silicon nanoparticles through its amino-rich branch chains;and the network utilizes the bonding reversibility of hydrogen and ionic bonds to repeatedly eliminate the mechanical stress and self-heal the structure damages caused by the volume change of silicon.Benefited from the multifunction of the dual crosslinked network,the silicon anode has achieved an excellent electrochemical performance with a specific capacity of 2403 mAh·g^(-1)at the current density of500 mA·g^(-1)after 100 cycles.