Kai Xin San ameliorates scopolamine-induced cognitive dysfunction

Kai Xin San(KXS, containing ginseng, hoelen, polygala, and acorus), a traditional Chinese herbal compound, has been found to regulate cognitive dysfunction; however, its mechanism of action is still unclear. In this study, 72 specific-pathogen-free male Kunming mice aged 8 weeks were randomly divided into a vehicle control group, scopolamine group, low-dose KXS group, moderate-dose KXS group, high-dose KXS group, and positive control group. Except for the vehicle control group and scopolamine groups(which received physiological saline), the doses of KXS(0.7, 1.4 and 2.8 g/kg per day) and donepezil(3 mg/kg per day) were gastrointestinally administered once daily for 2 weeks. On day 8 after intragastric treatment, the behavioral tests were carried out. Scopolamine group and intervention groups received scopolamine 3 mg/kg per day through intraperitoneal injection. The effects of KXS on spatial learning and memory, pathological changes of brain tissue, expression of apoptosis factors, oxidative stress injury factors, synapse-associated protein, and cholinergic neurotransmitter were measured. The results confirmed the following.(1) KXS shortened the escape latency and increased residence time in the target quadrant and the number of platform crossings in the Morris water maze.(2) KXS increased the percentage of alternations between the labyrinth arms in the mice of KXS groups in the Y-maze.(3) Nissl and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining revealed that KXS promoted the production of Nissl bodies and inhibited the formation of apoptotic bodies.(4) Western blot assay showed that KXS up-regulated the expression of anti-apoptotic protein Bcl-2 and inhibited the expression of pro-apoptotic protein Bax. KXS up-regulated the expression of postsynaptic density 95, synaptophysin, and brain-derived neurotrophic factor in the cerebral cortex and hippocampus.(5) KXS increased the level and activity of choline acetyltransferase, acetylcholine, superoxide dismutase, and glutathione peroxidase, and reduced the level and activity of acetyl cholinesterase, reactive oxygen species, and malondialdehyde through acting on the cholinergic system and reducing oxidative stress damage. These results indicate that KXS plays a neuroprotective role and improves cognitive function through reducing apoptosis and oxidative stress, and regulating synapse-associated protein and cholinergic neurotransmitters.

Bacterial infection triggers and complicates acute-on-chronic liver failure in patients with hepatitis B virus-decompensated cirrhosis: A retrospective cohort study

BACKGROUND Reports on bacterial infection(BI)in decompensated cirrhosis(DC)is mainly from alcoholic cirrhosis.The role of BI as a trigger or complication of acute-onchronic liver failure(ACLF)in patients with hepatitis B virus decompensated cirrhosis(HBV-DC)remains to be investigated.AIM To investigate the impact of BI on the outcomes of the patients with HBV-DC admitted into the hospital with or without ACLF.METHODS This retrospective study included patients with HBV-DC admitted to two tertiary centers in China.In-hospital overall survival,90-d transplant-free survival,5-year post-discharge survival,and cumulative incidence of ACLF were evaluated.Risk factors for death were analyzed considering liver transplantation as a competing event.RESULTS A total of 1281 hospitalized HBV-DC patients were included;284 had ACLF at admission.The overall prevalence of BI was 28.1%.The patients with BI had a significantly lower in-hospital survival and transplant-free 90-d survival than those without,in both the patients admitted with and without ACLF.The presence of BI significantly increased the risk of developing ACLF[subdistribution hazard ratio(sHR)=2.52,95%CI:1.75-3.61,P<0.001]in the patients without ACLF.In the patients discharged alive,those who had an episode of BI had a significantly lower 5-year transplant-free survival.BI was an independent risk factor for death in the patients admitted without ACLF(sHR=3.28,95%CI:1.93-5.57),while in ACLF admissions,the presence of pneumonia,but not other type of BI,independently increased the risk of death(sHR=1.87,95%CI:1.24-2.82).CONCLUSION BI triggers ACLF in patients with HBV-DC and significantly impairs short-term survival.HBV-DC patients should be monitored carefully for the development of BI,especially pneumonia,to avoid an adverse outcome.

The formation and repair of DNA double-strand breaks in mammalian meiosis

Programmed DNA double-strand breaks(DSBs)are necessary for meiosis in mammals.A sufficient number of DSBs ensure the normal pairing/synapsis of homologous chromosomes.Abnormal DSB repair undermines meiosis,leading to sterility in mammals.The DSBs that initiate recombination are repaired as crossovers and noncrossovers,and crossovers are required for correct chromosome separation.Thus,the placement,timing,and frequency of crossover formation must be tightly controlled.Importantly,mutations in many genes related to the formation and repair of DSB result in infertility in humans.These mutations cause nonobstructive azoospermia in men,premature ovarian insufficiency and ovarian dysgenesis in women.Here,we have illustrated the formation and repair of DSB in mammals,summarized major factors influencing the formation of DSB and the theories of crossover regulation.