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Objective: To study the hypoglycemic effect and mechanism of guar gum manno-oligosaccharides (GMOS) on streptozotocin-induced diabetic mice. Methods: GMOS was administered to diabetic mice for 6 weeks, and the changes in body mass and insulin resistance were monitored. Furthermore, indicators of glucose and lipid metabolism such as glucose (GLU), insulin (INS), high density lipoprotein cholesterol (HDL-C), and low density lipoprotein cholesterol (LDL-C) were determined. Hepatic histopathological changes were observed, and the expression of proteins involved in the adenosine monophosphate-activated protein kinase (AMPK)/peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) signaling pathway and the activity of antioxidant enzymes in the liver were detected. Results: GMOS effectively relieved the body mass loss of diabetic mice, significantly alleviated glucose tolerance (30.3%) and enhanced insulin sensitivity (34.6%). Compared with the model group, GMOS decreased the levels of GLU, glycosylated serum protein (GSP) and LDL-C by 38.6%, 29.5%, and 27.3%, respectively, and increased the levels of insulin and HDL-C significantly. Moreover, GMOS reduced oxidative damage, activated the AMPK/PGC-1α signaling pathway, and improved the activities of superoxide dismutase (SOD) and catalase (CAT) in the liver. Conclusion: GMOS could reduce blood glucose and mitigate glucose and lipid metabolism disorder and oxidative stress caused by diabetes mellitus, indicating its potential as a functional food ingredient against diabetes.

Objective: To analyze the clinical features and genetic changes of 3 children in short stature with ACAN gene mutation. Methods: The clinical data, laboratory examinations, and genetic testing results of 3 children with ACAN gene mutations diagnosed with short stature at our pediatric endocrine disease clinic from 2018 to 2020 were collected, and the literature was reviewed for analysis and summary. Results: All the three children had a short family history, and their clinical manifestations were short stature. One patient had a slight limitation of the flexion activity of the thoracolumbar spine, and no other system abnormalities were found. Among them, the oldest of the 3 children was 5 years and 1 month, and the bone age was roughly consistent with or slightly advanced than the actual age, and the peak growth hormone challenge in 2 cases was less than 10 μg/L. The variations in the ACAN gene are c.G1877A and c.7360, respectively_ 7361del and c.7038_ 7039insCGGTGT, case 1 and case 2 are novel mutations that have not been reported in major databases. After the application of recombinant human growth hormone, the height of all three children improved. Reviewing the literature at home and abroad, we found that there were 120 children and 216 relatives reported at present. Among them, there were 80 ACAN gene variants related to short stature registered in HGMD, of which short stature was the most important clinical manifestation, followed by skeletal dysplasia. Conclusions: Mutations of ACAN gene mainly lead to short stature and skeletal dysplasia in children, and their clinical bone phenotypes are diverse, which can also only be manifested as short stature. For children with short stature, especially those with short stature family history, no matter whether they have skeletal abnormalities, they should be alert to this gene mutation.

Objective: To explore the genotype and clinical phenotype of congenital generalized lipodystrophy type 1(CGL1), and to improve awareness of the disease. Methods: A patient with severe acanthosis nigricans was diagnosed as having CGL1, and the clinical information and results of laboratory and gene tests were analyzed. Five Chinese cases with CGL1 in the database were literaturally reviewed. Results: The patient was a girl(10 years and 11 months), who had significantly acanthosis nigricans and body subcutaneous fat loss. The examination of the girl showed hyperinsulinemia, impaired glucose tolerance, advanced bone age, low adiponectin and polycystic ovary. The compound heterozygous mutations were identified, which was c.646A>T:p.K216*(PVS1_Strong+ PM2+PM3 ( inherited from her father) and c.406G>A:p.G136R(PM3_Strong+PM1+PM2+PP3 (inherited from her mother) in AGPAT2 gene. The mutation of two gene loci could be pathogenic, which had not been reported in CNKI database. All 5 Chinese cases in CNKI database were reported before (including 2 males and 3 females, and age was between 66 days and 26 years old) showed the absence of adipose tissue, in which two patients presented severe acanthosis nigricans. Conclusions: The CGL1 is rare in Chinese population, and it should be considered as the patients present the acanthosis nigricans and absence of adipose tissue, and its diagnosis depends gene detection.

Auto-inhibited Ca 2+ -ATPase (ACA) is one of the Ca 2+ -ATPase subfamilies that plays an important role in maintaining Ca 2+ concentration balance in plant cells. To explore the function and gene expression pattern of the RcACA gene family in castor, bioinformatics analysis was used to identify the members of the RcACA gene family in castor. The basic physical and chemical properties, subcellular location, protein secondary and tertiary structure, conserved domain, conserved motif, gene structure, chromosome location and collinear relationship, as well as the evolutionary characteristics and promoter cis -acting elements were predicted and analyzed. The expression pattern of the RcACA gene under abiotic stress was analyzed by expression (fragments per kilobase of exon model per million mapped fragments, FPKM) in castor transcriptome data. The results showed that 8 RcACA gene family members were identified in castor, acidic proteins located in the plasma membrane. In the secondary structure of all proteins, the α-helix and random coil is more; the RcACA genes were clustered into three categories, and the design of the genes in the same category was similar to the conserved motif. Both of them had four typical domains, RcACA3 - RcACA8 had a Ca 2+ -ATPase N-terminal autoinhibitory domain. The RcACA gene is mostly located on the long arm of the chromosome and has 2 pairs of collinear relationships. There are more light response elements but fewer hormone-induced elements located upstream of the RcACA coding region. Interspecific clustering showed that the evolution of ACA genes among species was conservative. Tissue expression pattern analysis showed that RcACA genes showed apparent tissue expression specificity, and most of the genes showed the highest expression level in male flowers. Expression analysis under abiotic stress showed that RcACA2 - RcACA8 were up-regulated under high salt and drought stress, and RcACA1 was up-regulated at 0-24 h under low-temperature stress, indicating that RcACA genes positively responded to abiotic stresses. The above results provide a theoretical basis for exploring the role of the RcACA gene in castor growth, development and stress response.