Objective:To investigate the clinical, phenotypic and genotypic features of hereditary hyperhomocysteinemia mainly involving the nervous system.Methods:The clinical data, physical examination, imaging results, blood-urine tandem mass spectrometry analysis and genetic results of 8 patients with hyperhomocysteinemia from the Department of Neurology of the Shanghai Sixth People′s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from September 2020 to December 2023 were collected, and the clinical, genetic features and pathogenic mechanisms of these patients were summarized and analyzed.Results:Among all the 8 patients (male∶female=5∶3), the age of onset was 7 to 74 (40.4±7.4) years. Seven had adult-onset and 1 had juvenile-onset, with various types of onset symptoms, including progressive stiffness in lower limbs and walking difficulty, limb numbness, tremor, mental and behavioral abnormalities, cerebrovascular events, etc. Moderate to severe hyperhomocysteine (38.4-190.6 μmol/L) was present in all patients at first diagnosis. Among the 5 patients with cranial imaging examinations, all had white matter lesions. The genetic testing showed 7 patients with MTHFR gene pathogenic mutations (1 case with c.416C>T, and 6 cases with c.665C>T), and 1 patient with MMACHC gene pathogenic mutation (c.482G>A). Conclusions:Hereditary hyperhomocysteinemia is a metabolic disease, with complicated manifestations, varying degrees of severity, and diverse pathogenic genes. The cases with neurological involvement are not rare, such as spastic paraplegia-like manifestations, tremor, peripheral neuropathy, mental and behavioral abnormalities, cerebrovascular events.

Objective:To investigate the clinical, phenotypic and genotypic features of hereditary hyperhomocysteinemia mainly involving the nervous system.Methods:The clinical data, physical examination, imaging results, blood-urine tandem mass spectrometry analysis and genetic results of 8 patients with hyperhomocysteinemia from the Department of Neurology of the Shanghai Sixth People′s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from September 2020 to December 2023 were collected, and the clinical, genetic features and pathogenic mechanisms of these patients were summarized and analyzed.Results:Among all the 8 patients (male∶female=5∶3), the age of onset was 7 to 74 (40.4±7.4) years. Seven had adult-onset and 1 had juvenile-onset, with various types of onset symptoms, including progressive stiffness in lower limbs and walking difficulty, limb numbness, tremor, mental and behavioral abnormalities, cerebrovascular events, etc. Moderate to severe hyperhomocysteine (38.4-190.6 μmol/L) was present in all patients at first diagnosis. Among the 5 patients with cranial imaging examinations, all had white matter lesions. The genetic testing showed 7 patients with MTHFR gene pathogenic mutations (1 case with c.416C>T, and 6 cases with c.665C>T), and 1 patient with MMACHC gene pathogenic mutation (c.482G>A). Conclusions:Hereditary hyperhomocysteinemia is a metabolic disease, with complicated manifestations, varying degrees of severity, and diverse pathogenic genes. The cases with neurological involvement are not rare, such as spastic paraplegia-like manifestations, tremor, peripheral neuropathy, mental and behavioral abnormalities, cerebrovascular events.

AIM:To study lipopolysaccharide (LPS)-stimulated secretion of endothelin-1 (ET-1) and adrenomedullin (Adm) from human vascular endothelial cells (HVEC) and its mechanism. METHODS:In cultured HVEC, LPS was used to stimulate ET-1 and Adm secretion from HVEC. The contents of ET-1 and Adm in medium were determined by radioimmunoassay. RESULTS:LPS stimulated secretion of ET-1 and Adm from HVEC in time-dependent and concentration-dependent manner. The ratio of secreted ET-1 to Adm was not changed compared with the control group. The increase of ET-1 could be inhibited by inhibitor of extracellular signal-regulated protein kinases (PD098059) and inhibitor of P38 kinase (SB202190)（P＜0.01）, while the increase of Adm could only be inhibited by SB202190（P＜0.05）, both had no response to inhibitor of protein kinase C (H7), inhibitor of calmodulin (W7), inhibitor of calcineurin (cyclosporin A) and inhibitor of Ca2+ (nicardipine)（P＞0.05）.CONCLUSION:ERKs and P38 signal pathways may play an important role in the secretion of ET-1 from LPS -stimulated HVEC, while only P38 kinase signal pathway is invovled in the secretion of Adm.

AIM: To study the effect of chronic hypoxia on L-Arginine/NO pathway in rat pulmonary artery. METHODS: Changes in pulmonary artery L-Arginine(L-Arg) transport, nitric oxide synthase (NOS) activity, plasma nitrite level and L-Arg level in HPH rats were investigated. RESULTS: (1) The mean pulmonary arterial pressure (mPAP) and weight ratio of right ventricle to left ventricle and septum (RV/LV+S) of HPH group were higher than those in control group (P

AIM: To study lipopolysaccharide (LPS)-stimulated secretion of endothelin-1 (ET-1) and adrenomedullin (Adm) from human vascular endothelial cells (HVEC) and its mechanism. METHODS: In cultured HVEC, LPS was used to stimulate ET-1 and Adm secretion from HVEC. The contents of ET-1 and Adm in medium were determined by radioimmunoassay. RESULTS: LPS stimulated secretion of ET-1 and Adm from HVEC in time-dependent and concentration-dependent manner. The ratio of secreted ET-1 to Adm was not changed compared with the control group. The increase of ET-1 could be inhibited by inhibitor of extracellular signal-regulated protein kinases (PD 098059 ) and inhibitor of P38 kinase (SB 202190 )( P 0.05).CONCLUSION: ERKs and P38 signal pathways may play an important role in the secretion of ET-1 from LPS -stimulated HVEC, while only P38 kinase signal pathway is invovled in the secretion of Adm.