Interaction between catechol-O-methyltransferase Val/Met polymorphism and cognitive reserve for negative symptoms in schizophrenia

BACKGROUND Cognitive reserve(CR)and the catechol-O-methyltransferase(COMT)Val/Met polymorphism are reportedly linked to negative symptoms in schizophrenia.However,the regulatory effect of the COMT genotype on the relationship between CR and negative symptoms is still unexamined.AIM To investigate whether the relationship between CR and negative symptoms could be regulated by the COMT Val/Met polymorphism.METHODS In a cross-sectional study,54 clinically stable patients with schizophrenia underwent assessments for the COMT genotype,CR,and negative symptoms.CR was estimated using scores in the information and similarities subtests of a short form of the Chinese version of the Wechsler Adult Intelligence Scale.RESULTS COMT Met-carriers exhibited fewer negative symptoms than Val homozygotes.In the total sample,significant negative correlations were found between negative symptoms and information,similarities.Associations between information,similarities and negative symptoms were observed in Val homozygotes only,with information and similarities showing interaction effects with the COMT genotype in relation to negative symptoms(information,β=-0.282,95%CI:-0.552 to-0.011,P=0.042;similarities,β=-0.250,95%CI:-0.495 to-0.004,P=0.046).CONCLUSION This study provides initial evidence that the association between negative symptoms and CR is under the regulation of the COMT genotype in schizophrenia.

Chinese herbal formula shen-ling-bai-zhu-san to treat chronic gastritis: Clinical evidence and potential mechanisms

BACKGROUND Chronic gastritis(CG) is an inflammatory disease of the gastric mucosa. Shenling-bai-zhu san(SLBZS), a traditional Chinese medicine formula, is widely used for treating CG. Nevertheless, its effects are currently unclear.AIM To determine the clinical evidence and potential mechanisms of SLBZS for the treatment of CG.METHODS We systematically searched 3 English(PubMed, Embase, Medline) and 4 Chinese databases(Cochrane Library Central Register of Controlled Trials, China National Knowledge Infrastructure database, Wanfang Data Knowledge Service Platform,and the VIP information resource integration service platform) without language or publication bias restriction. Qualified studies were selected according to pre-set inclusion and exclusion criteria. RevMan 5.3 software was used for meta-analysis and literature quality assessment, Stata 14.0 software was used for sensitivity analysis, GRADE profiler 3.6 was used to evaluate the quality of evidence. And then, network pharmacology analysis was applied to primary research the mechanisms of action of SLBZS on CG.RESULTS Fourteen studies were finally included, covering 1335 participants. Meta-analysis indicated that:(1) SLBZS was superior to conventional therapies [risk ratio(RR):1.29, 95% confidence interval(CI): 1.21 to 1.37, P < 0.00001];(2) SLBZS was better than conventional therapies [RR: 0.24, 95% confidence interval(95%CI): 0.11 to 0.55, P = 0.0007] in terms of recurrence rate and reversal of Helicobacter pylori positivity(RR: 1.20, 95%CI: 1.11 to 1.30,P < 0.00001);and(3) The safety of SLBZS for CG remains unclear. According to the GRADE method, the quality of evidence was not high. Besides, SNZJS might treat CG by acting on related targets and pathways such as EGFR tyrosine kinase inhibitor resistance, the PI3K-Akt signaling pathway, and others.CONCLUSION SLBZS might be useful in treating CG, but long-term effects and specific clinical mechanisms of it maintain unclear. More samples and high-quality clinical experiments should be assessed and verified in the next step.

Effects of histamine on spontaneous neuropathic pain induced by peripheral axotomy

The present study was designed to investigate the effects of histamine on spontaneous neuropathic pain （NP） induced by peripheral axotomy. Rats and mice were subjected to complete transection of the left sciatic and saphenous nerves to induce spontaneous NP （the neuroma model）. Rats were then treated with drugs once daily for 30 days （histidine and Ioratadine, i.p.） or 21 days （histamine, i.c.v.）. Autotomy behavior was scored daily until day 50 postoperation （PO）. On days 14 to 21 PO, some rats in the control group were subjected to singlefiber recording. Autotomy behavior was also monitored daily in histidine decarboxylase （the key enzyme for histamine synthesis） knockout （HDC/） and wildtype mice for 42 days. We found that both histidine （500 mg/kg） （a precursor of histamine that increases histamine levels in the tissues） and histamine （50 pg/5 pL） significantly suppressed autotomy behavior in rats. HDC mice lacking endogenous histamine showed higher levels of autotomy than the wildtype. In addition, the analgesic effect of histidine was not antagonized by Ioratadine （a peripherallyacting H1 receptor antago nist）, while Ioratadine alone significantly suppressed autotomy. Electrophysiological recording showed that ectopic spontaneous discharges from the neuromawere blocked by systemic diphenhydramine （an H receptor antagonist）. Our results suggest that hista mine plays an important role in spontaneous NP. It is likely that histamine in the central nervous system is analgesic, while in the periphery, via H receptors, it is algesic. This study justifies the avoidance of a histaminerich diet and the use of peripherallyacting H receptor antagonists as well as agents that improve histamine action in the central nervous system in pa tients with spontaneous NP.