BACKGROUND:Studies at home and abroad have shown that sarcopenia is closely related to metabolites.At present,the relationship between the latest 1400 blood metabolites and sarcopenia is still unknown.OBJECTIVE:To analyze the causal relationship between 1 400 metabolites and sarcopenia and its relevance with cardiovascular disease using Mendelian randomization.METHODS:Genome-wide association study(GWAS)data of sarcopenia-related characteristics(grip strength,limb muscle lean body mass,and walking speed)were obtained from the OPEN GWAS website as outcome data.A GWAS containing 1 400 metabolites was used as an exposure factor,and single nucleotide polymorphisms significantly associated with exposure factors were selected as instrumental variables.The causal association between 1 400 metabolites and sarcopenia was analyzed by"TwoSampleMR"and"gwasglue"packages of R software(V4.3.2).The research methods included inverse variance weighting,MR-Eggeer regression intercept,weighted median method,and simple mode.Heterogeneity,pleiotropic,sensitivity and other verification analysis were performed.Finally,reverse Mendelian randomization analysis was performed.RESULTS AND CONCLUSION:(1)The causal relationship between 1 400 serum metabolites and sarcopenia was analyzed by inverse variance weighting.The results showed that 1-linoleoyl-2-linoleoyl-GPC(18:2/18:3)and glycodeoxycholate 3-sulfate were protective factors,and the risk of disease decreased with the increase of metabolites(P＜0.01).(2)Two unknown metabolites(X-12822 and X-15486)and trans-3,4-methyleneheptanoate were risk factors.With the increase of two unknown metabolites(X-12822 and X-15486),the degree of low grip strength of male hands increased.Similarly,with the increase of trans-3,4-methylene heptanoate,the risk of disease also increased(P＜0.01).(3)To conclude,1-linoleoyl-2-linoleoyl-GPC(18:2/18:3)and glycodeoxycholate 3-sulfate have inhibitory effects on sarcopenia.Two unknown metabolites(X-12822 and X-15486)and trans-3,4-methyleneheptanoate can promote sarcopenia.This may be a new idea and new basis for sarcopenia research and treatment in the future.This study will also provide a reference for the study of the role of related metabolites in the Chinese population.

BACKGROUND:Studies at home and abroad have shown that sarcopenia is closely related to metabolites.At present,the relationship between the latest 1400 blood metabolites and sarcopenia is still unknown.OBJECTIVE:To analyze the causal relationship between 1 400 metabolites and sarcopenia and its relevance with cardiovascular disease using Mendelian randomization.METHODS:Genome-wide association study(GWAS)data of sarcopenia-related characteristics(grip strength,limb muscle lean body mass,and walking speed)were obtained from the OPEN GWAS website as outcome data.A GWAS containing 1 400 metabolites was used as an exposure factor,and single nucleotide polymorphisms significantly associated with exposure factors were selected as instrumental variables.The causal association between 1 400 metabolites and sarcopenia was analyzed by"TwoSampleMR"and"gwasglue"packages of R software(V4.3.2).The research methods included inverse variance weighting,MR-Eggeer regression intercept,weighted median method,and simple mode.Heterogeneity,pleiotropic,sensitivity and other verification analysis were performed.Finally,reverse Mendelian randomization analysis was performed.RESULTS AND CONCLUSION:(1)The causal relationship between 1 400 serum metabolites and sarcopenia was analyzed by inverse variance weighting.The results showed that 1-linoleoyl-2-linoleoyl-GPC(18:2/18:3)and glycodeoxycholate 3-sulfate were protective factors,and the risk of disease decreased with the increase of metabolites(P＜0.01).(2)Two unknown metabolites(X-12822 and X-15486)and trans-3,4-methyleneheptanoate were risk factors.With the increase of two unknown metabolites(X-12822 and X-15486),the degree of low grip strength of male hands increased.Similarly,with the increase of trans-3,4-methylene heptanoate,the risk of disease also increased(P＜0.01).(3)To conclude,1-linoleoyl-2-linoleoyl-GPC(18:2/18:3)and glycodeoxycholate 3-sulfate have inhibitory effects on sarcopenia.Two unknown metabolites(X-12822 and X-15486)and trans-3,4-methyleneheptanoate can promote sarcopenia.This may be a new idea and new basis for sarcopenia research and treatment in the future.This study will also provide a reference for the study of the role of related metabolites in the Chinese population.

Objective To investigate the correlation between the level of presenilin-associated rhomboidlike protein (PARL) and the sperm motility,survival rate and deformity rate of sperm in workers exposed to aluminum.Methods A total of 162 male workers exposed to aluminum in a large aluminum enterprise in Guangxi were selected as the exposure group,and the 162 staff members of the service company were selected as the control group by matching the age and length of service.The concentration of aluminum in the working environment and the aluminum content in the blood and urine were determined by graphite furnace atomic absorption spectrometry and high performance liquid chromatography.Enzyme linked immunosorbent assay was used to measure the level of PARL protein in sperm and sperm function was evaluated.Results The average concentrations of aluminum in the batching,electrolysis and casting of aluminum exposure group were (6.72± 1.45),(7.23± 1.50) and (7.35± 1.72)mg/m3,which were significantly higher than those of the control group (F=8.314,P＜0.001).The content of aluminum in blood and urine of exposed group were significantly higher than those of control group (P＜0.05),while the levels of PARL of exposed group were significantly lower than those of control group (P＜0.05).Moreover,the sperm survival rate and sperm motility of exposed group were significantly lower than those of the control group,and the sperm deformity rates of exposed group were significantly higher than those of the control group(P＜0.05).Pearson correlation analysis showed that there was a positive correlation of sperm motility,sperm survival rate and protein level of PARL (rsprm motility=0.713,P=0.012;rsperm survival rate =0.628,P=0.008);while the sperm deformity rate and protein level of PARL showed a significant negative correlation (rsperm deformity rate =0.953,P =0.002).Conclusion The sperm function was significantly impaired in aluminum exposed workers,and the changes of sperm motility,survival rate and malformation rate were closely related to the protein level of PARL.