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11.
Whole-body volatiles from males of the cryptic multimammate mouse speciesMastomys natalensis andM. coucha were analyzed by dynamic solvent effect sampling and capillary gas chromatography. One compound, 3-nonene-2-one, was always present, sometimes as the major component, in volatiles fromM. coucha and absent, or present only at low levels, in volatiles fromM. natalensis. The mean ±SD of the 3-nonen-2-one peak area forM. coucha was 8599 ±9630 and forM. natalensis 148 ±486. Chromatographic analysis was more reliable in identifying a male's species than were a female's in a two-choice olfactorium.  相似文献   
12.
该文探究毛菊苣醇提物对糖尿病小鼠(db/db小鼠)肠道菌群的影响。该研究以m/m小鼠为正常对照组(CON组),db/db小鼠随机分为模型组(MOD组)、二甲双胍组(MET组)、毛菊苣醇提物低剂量组(CGL组)、毛菊苣醇提物高剂量组(CGH组)。灌胃给药8周,对小鼠体质量、空腹血糖、肝脏总胆固醇(TC)、甘油三酯(TG)进行分析,对小鼠粪便进行16S rRNA测序分析,探究毛菊苣醇提物对小鼠肠道菌群的影响。毛菊苣醇提物高剂量组可调节db/db小鼠体质量及血糖,显著降低db/db小鼠TC、TG水平(P<0.05);测序结果显示CON组、MOD组、CGH组三组小鼠肠道菌群情况存在差异,毛菊苣醇提物给药可改善db/db 小鼠的肠道菌群失调,上调db/db小鼠肠道菌群中有益菌双歧杆菌属(Bifidobacterium)、Romboutsia、普雷沃氏菌属(Prevotella)菌群相对丰度。研究证明了毛菊苣醇提物给药能调节db/db小鼠肠道菌群,通过提高有益菌相对丰度调节糖脂代谢,可为新疆地产毛菊苣药材资源的开发利用提供全新的研究思路。  相似文献   
13.
Post-translational modifications (PTMs) have been confirmed to be involved in multiple female reproductive events, but their role in physiological ovarian aging is far from elucidated. In this study, mice aged 3, 12 or 17 months (3M, 12M, 17M) were selected as physiological ovarian aging models. The expression of female reproductive function-related genes, the global profiles of PTMs, and the level of histone modifications and related regulatory enzymes were examined during physiological ovarian aging in the mice by quantitative real-time PCR and western blot, respectively. The results showed that the global protein expression of Kbhb (lysineβ-hydroxybutyryllysine), Khib (lysine 2-hydroxyisobutyryllysine), Kglu (lysineglutaryllysine), Kmal (lysinemalonyllysine), Ksucc (lysinesuccinyllysine), Kcr (lysinecrotonyllysine), Kbu (lysinebutyryllysine), Kpr (lysinepropionyllysine), SUMO1 (SUMO1 modification), ub (ubiquitination), P-Typ (phosphorylation), and 3-nitro-Tyr (nitro-tyrosine) increased significantly as mice aged. Moreover, the modification level of Kme2 (lysinedi-methyllysine) and Kac (lysineacetyllysine) was the highest in the 3M mice and the lowest in 12M mice. In addition, only trimethylation of histone lysine was up-regulated progressively and significantly with increasing age (p < 0.001), H4 ubiquitination was obviously higher in the 12M and 17M mice than 3M (p < 0.001), whereas the modification of Kpr (lysinepropionylation) and O-GlcNA in 17M was significantly decreased compared with the level in 3M mice (p < 0.05, p < 0.01). Furthermore, the expression levels of the TIP60, P300, PRDM9, KMT5B, and KMT5C genes encoding PTM regulators were up-regulated in 17M compared to 3M female mice (p < 0.05). These findings indicate that altered related regulatory enzymes and PTMs are associated with physiological ovarian aging in mice, which is expected to provide useful insights for the delay of ovarian aging and the diagnosis and treatment of female infertility.  相似文献   
14.
15.
Herbal remedies are increasing in popularity as treatments for metabolic conditions such as obesity and Type 2 Diabetes. One potential therapeutic option is fenugreek seeds (Trigonella foenum-graecum), which have been used for treating high cholesterol and Type 2 diabetes. A proposed mechanism for these benefits is through alterations in the microbiome, which impact mammalian host metabolic function. This study used untargeted metabolomics to investigate the fenugreek-induced alterations in the intestinal, liver, and serum profiles of mice fed either a 60% high-fat or low-fat control diet each with or without fenugreek supplementation (2% w/w) for 14 weeks. Metagenomic analyses of intestinal contents found significant alterations in the relative composition of the gut microbiome resulting from fenugreek supplementation. Specifically, Verrucomicrobia, a phylum containing beneficial bacteria which are correlated with health benefits, increased in relative abundance with fenugreek. Metabolomics partial least squares discriminant analysis revealed substantial fenugreek-induced changes in the large intestines. However, it was observed that while the magnitude of changes was less, significant modifications were present in the liver tissues resulting from fenugreek supplementation. Further analyses revealed metabolic processes affected by fenugreek and showed broad ranging impacts in multiple pathways, including carnitine biosynthesis, cholesterol and bile acid metabolism, and arginine biosynthesis. These pathways may play important roles in the beneficial effects of fenugreek.  相似文献   
16.
Heparan sulfate (HS) is a type of glycosaminoglycan that plays a key role in a variety of biological functions in neurology, skeletal development, immunology, and tumor metastasis. Biosynthesis of HS is initiated by a link of xylose to Ser residue of HS proteoglycans, followed by the formation of a linker tetrasaccharide. Then, an extension reaction of HS disaccharide occurs through polymerization of many repetitive units consisting of iduronic acid and N-acetylglucosamine. Subsequently, several modification reactions take place to complete the maturation of HS. The sulfation positions of N-, 2-O-, 6-O-, and 3-O- are all mediated by specific enzymes that may have multiple isozymes. C5-epimerization is facilitated by the epimerase enzyme that converts glucuronic acid to iduronic acid. Once these enzymatic reactions have been completed, the desulfation reaction further modifies HS. Apart from HS biosynthesis, the degradation of HS is largely mediated by the lysosome, an intracellular organelle with acidic pH. Mucopolysaccharidosis is a genetic disorder characterized by an accumulation of glycosaminoglycans in the body associated with neuronal, skeletal, and visceral disorders. Genetically modified animal models have significantly contributed to the understanding of the in vivo role of these enzymes. Their role and potential link to diseases are also discussed.  相似文献   
17.
Connexin37 (Cx37) and Cx40 form intercellular channels between endothelial cells (EC), which contribute to the regulation of the functions of vessels. We previously documented the participation of both Cx in developmental angiogenesis and have further shown that loss of Cx40 decreases the growth of different tumors. Here, we report that loss of Cx37 reduces (1) the in vitro proliferation of primary human EC; (2) the vascularization of subcutaneously implanted matrigel plugs in Cx37−/− mice or in WT using matrigel plugs supplemented with a peptide targeting Cx37 channels; (3) tumor angiogenesis; and (4) the growth of TC-1 and B16 tumors, resulting in a longer mice survival. We further document that Cx37 and Cx40 function in a collaborative manner to promote tumor growth, inasmuch as the injection of a peptide targeting Cx40 into Cx37−/− mice decreased the growth of TC-1 tumors to a larger extent than after loss of Cx37. This loss did not alter vessel perfusion, mural cells coverage and tumor hypoxia compared to tumors grown in WT mice. The data show that Cx37 is relevant for the control of EC proliferation and growth in different tumor models, suggesting that it may be a target, alone or in combination with Cx40, in the development of anti-tumoral treatments.  相似文献   
18.
19.
Approximately 50–80% of children with autism spectrum disorders (ASDs) exhibit sleep problems, but the contribution of circadian clock dysfunction to the development of ASDs remains largely unknown. The essential clock gene Bmal1 (Arntl or Mop3) has been associated with human sociability, and its missense mutation is found in ASD. Our recent study found that Bmal1-null mice exhibit a variety of autism-like phenotypes. Here, we further investigated whether an incomplete loss of Bmal1 function could cause significant autism-like behavioral changes in mice. Our results demonstrated that heterozygous Bmal1 deletion (Bmal1+/−) reduced the Bmal1 protein levels by ~50–75%. Reduced Bmal1 expression led to decreased levels of clock proteins, including Per1, Per2, Cry 1, and Clock but increased mTOR activities in the brain. Accordingly, Bmal1+/− mice exhibited aberrant ultrasonic vocalizations during maternal separation, deficits in sociability and social novelty, excessive repetitive behaviors, impairments in motor coordination, as well as increased anxiety-like behavior. The novel object recognition memory remained intact. Together, these results demonstrate that haploinsufficiency of Bmal1 can cause autism-like behavioral changes in mice, akin to those identified in Bmal1-null mice. This study provides further experimental evidence supporting a potential role for disrupted clock gene expression in the development of ASD.  相似文献   
20.
The current study evaluated the glucose-lowering effect of ganoderma lucidum polysaccharides (Gl-PS) in streptozotocin (STZ)-induced diabetic mice. The diabetic mice were randomly divided into four groups (8 mice per group): diabetic control group, low-dose Gl-PS treated group (50 mg/kg, Gl-PS), high-dose Gl-PS treated group (150 mg/kg, Gl-PS) and positive drug control treated group (glibenclamide, 4 mg/kg), with normal mice used as the control group. Body weights, fasting blood glucose (FBG), serum insulin and blood lipid levels of mice were measured. After 28 days of treatment with Gl-PS, body weights and serum insulin levels of the Gl-PS treated groups was significantly higher than that of the diabetic control group, whereas FBG levels was significantly lower. Moreover, total cholesterol (TC), triglyceride (TG) and low density lipoprotein cholesterol (LDL-C) levels of the Gl-PS treated groups had dropped, whereas the high density lipoprotein cholesterol (HDL-C) levels had increased. In addition, according to acute toxicity studies, Gl-PS did not cause behavioral changes and any death of mice. These data suggest that Gl-PS has an antihyperglycemic effect. Furthermore, considering the Gl-PS effects on lipid profile, it may be a potential hypolipidaemic agent, which will be a great advantage in treating diabetic conditions associated with atherosclerosis or hyperlipidemia.  相似文献   
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