DL-3-n-butylphthalide improved physical and learning and memory performance of rodents exposed to acute and chronic hypobaric hypoxia

Background:Studies have revealed the protective effect of DL-3-n-butylphthalide(NBP)against diseases associated with ischemic hypoxia.However,the role of NBP in animals with hypobaric hypoxia has not been elucidated.This study investigated the effects of NBP on rodents with acute and chronic hypobaric hypoxia.Methods:Sprague-Dwaley rats and Kunming mice administered with NBP(0,60,120,and 240 mg/kg for rats and 0,90,180,and 360 mg/kg for mice)were placed in a hypobaric hypoxia chamber at 10,000 m and the survival percentages at 30 min were determined.Then,the time and distance to exhaustion of drug-treated rodents were evaluated during treadmill running and motor-driven wheel-track treadmill experiments,conducted at 5800 m for 3 days or 20 days,to evaluate changes in physical functions.The frequency of active escapes and duration of active escapes were also determined for rats in a shuttle-box experiment,conducted at 5800 m for 6 days or 27 days,to evaluate changes in learning and memory function.ATP levels were measured in the gastrocnemius muscle and malonaldehyde(MDA),superoxide dismutase(SOD),hydrogen peroxide(H_(2)O_(2)),glutathione peroxidase(GSH-Px),and lactate were detected in sera of rats,and routine blood tests were also performed.Results:Survival analysis at 10,000 m indicated NBP could improve hypoxia tolerance ability.The time and distance to exhaustion for mice(NBP,90 mg/kg)and time to exhaustion for rats(NBP,120 and 240 mg/kg)significantly increased under conditions of acute hypoxia compared with control group.NBP treatment also significantly increased the time to exhaustion for rats when exposed to chronic hypoxia.Moreover,240 mg/kg NBP significantly increased the frequency of active escapes under conditions of acute hypoxia.Furthermore,the levels of MDA and H_(2)O_(2) decreased but those of SOD and GSH-Px in the sera of rats increased under conditions of acute and chronic hypoxia.Additionally,ATP levels in the gastrocnemius muscle significantly increased,while lactate levels in sera significantly decreased.Conclusion:NBP improved physical and learning and memory functions in rodents exposed to acute or chronic hypobaric hypoxia by increasing their anti-oxidative capacity and energy supply.

Injectable cartilage matrix hydrogel loaded with cartilage endplate stem cells engineered to release exosomes for non-invasive treatment of intervertebral disc degeneration

Low back pain,mainly caused by intervertebral disc degeneration(IVDD),is a common health problem;however,current surgical treatments are less than satisfactory.Thus,it is essential to develop novel non-invasive surgical methods for IVDD treatment.Here,we describe a therapeutic strategy to inhibit IVDD by injecting hydrogels modified with the extracellular matrix of costal cartilage(ECM-Gels)that are loaded with cartilage endplate stem cells(CESCs).After loaded with CESCs overexpressing Sphk2(Lenti-Sphk2-CESCs)and injected near the cartilage endplate(CEP)of rats in vivo,ECM-Gels produced Sphk2-engineered exosomes(Lenti-Sphk2-Exos).These exosomes penetrated the annulus fibrosus(AF)and transported Sphk2 into the nucleus pulposus cells(NPCs).Sphk2 activated the phosphatidylinositol 3-kinase(PI3K)/p-AKT pathway as well as the intracellular autophagy of NPCs,ultimately ameliorating IVDD.This study provides a novel and efficient non-invasive combinational strategy for IVDD treatment using injectable ECM-Gels loaded with CESCs that express Sphk2 with sustained release of functional exosomes.

Knockdown of hepatocyte Perilipin-3 mitigates hepatic steatosis and steatohepatitis caused by hepatocyte CGI-58 deletion in mice

Comparative gene identification-58(CGI-58),also known asα/βhydrolase domain containing 5,is the co-activator of adipose triglyceride lipase that hydrolyzes triglycerides stored in the cytosolic lipid droplets.Mutations in CGI-58 gene cause Chanarin-Dorfman syndrome(CDS),an autosomal recessive neutral lipid storage disease with ichthyosis.The liver pathology of CDS manifests as steatosis and steatohepatitis,which currently has no effective treatments.Perilipin-3(Plin3)is a member of the Perilipin-ADRP-TIP47 protein family that is essential for lipid droplet biogenesis.The objective of this study was to test a hypothesis that deletion of a major lipid droplet protein alleviates fatty liver pathogenesis caused by CGI-58 deficiency in hepatocytes.Adult CGI-58-floxed mice were injected with adeno-associated vectors simultaneously expressing the Cre recombinase and microRNA against Plin3 under the control of a hepatocyte-specific promoter,followed by high-fat diet feeding for 6 weeks.Liver and blood samples were then collected from these animals for histological and biochemical analysis.Plin3 knockdown in hepatocytes prevented steatosis,steatohepatitis,and necroptosis caused by hepatocyte CGI-58 deficiency.Our work is the first to show that inhibiting Plin3 in hepatocytes is sufficient to mitigate hepatocyte CGI-58 deficiency-induced hepatic steatosis and steatohepatitis in mice.

FAP senescence:a critical event in muscle regeneration

In a recent study published in Nature,Moiseeva and colleagues examined senescent cells,including fibro/adipogenic progenitors(FAPs),muscle stem cells(MuSCs)and macrophages,which generate an inflammatory and fibrotic niche,thus inhibiting the activation of MuSCs and muscle regeneration.1 The researchers developed a method to distinguish endogenous senescent cells and showed the importance of cellular senescence as a potential target for improving muscle regeneration and repair(Fig.1).^(1)