ABSTRACT
Background Chronic low-level exposure to lead can damage the central nervous system and cause anxiety-like behavior. However, whether changes of blood metabolites occur in this process and its relationship with lead-induced neurobehavioral disorder remain unclear. Objective To explore the effects of chronic lead acetate (PbAc) exposure at different concentrations on anxiety-like behavior and serum metabolites and their relationships in mice, as well as the mechanism of lead exposure on neurobehavioral injury in mice from the perspective of metabolomics. Methods A total of 64 healthy 4-week-old C57BL/6J mice, half male and half female, were randomly divided into four groups: control group (normal drinking water), 20 mg·L−1 PbAc group, 100 mg·L−1 PbAc group, and 500 mg·L−1 PbAc group. After 10 weeks of free drinking of water containing designed concentrations of PbAc, the mice were tested for anxiety-like behavioral changes by open field experiment. After the mice were anesthetized, blood was collected from the eyes, the serum was separated, and the effects of designed doses of lead exposure on metabolites in the serum of mice were compared by liquid chromatography with tandem mass spectrometry combined with principal component analysis and partial least squares discrimination analysis. Results The results of the open field experiment showed that the reductions in movement time spent in central area in the 100 mg·L−1 and 500 mg·L−1 PbAc groups compared with the control group were of statistical significance (P<0.05); the reduction in crossing times of central region in the 500 mg·L−1 PbAc group was statistically significant compared with the control group (P<0.05); the increases in defecation frequency in the 100 mg·L−1 and 500 mg·L−1 PbAc groups were statistically significant compared to the control group (P<0.05). In both positive and negative ion modes, compared with the control group, 157 differential metabolites were screened out in the 20 mg·L−1 PbAc group, of which 80 were up-regulated and 77 were down-regulated; 172 differential metabolites were screened out in the 100 mg·L−1 PbAc group, of which 57 were up-regulated and 115 were down-regulated; 119 differential metabolites were screened out in the 500 mg·L−1 PbAc group, of which 42 were up-regulated and 77 were down-regulated. The results of the KEGG enrichment analysis on the differential metabolites revealed alterations in metabolic pathways mainly involving primary bile acid biosynthesis, bile secretion, and cholesterol metabolism. Among the differential metabolites, norethisterone was positively correlated with the number of central region crossings (r=0.406, P<0.05); dihydrothymine was negatively correlated with the number of central region crossings (r=−0.346, P<0.05); lysophosphatidylcholine 22∶1 and lysophospholipid 14∶0 were negatively correlated with time spent in central region (r=−0.429, P<0.05; r=−0.374, P<0.05). Conclusion Chronic lead exposure induces anxiety-like behavior in mice, and this altered behavior is associated with altered metabolites in serum, with differential metabolites enriched primarily in the metabolic pathways of primary bile acid biosynthesis, bile acid secretion, and cholesterol metabolism.
ABSTRACT
Objective To compare and analyze the index variation of Yang deficiency mice induced by hydrocortisone in different way of administration and dose. Methods The mice model of Yang deficiency were induced by low dose and high dose hydrocortisone(12.5 mg/kg, 25 mg/kg) in two ways of intramuscular and intraperitoneal injection. The symptoms, body weight, the average intake, the index of stress and the coefficient of sex organs and immune organs of animals were observed. Results In the way of intraperitoneal injection, the weight(24.52±3.29)g, body temperature(35.24±0.32)℃ of high dose of model group were significantly lower than that of control group(31.10±6.11)g,(37.02±0.64)℃. The average intake of low dose group(4.30 ± 0.29)g/(per?d) was lower than control group(7.38±0.53)g/(per?d), and the coefficient of preputial glands(0.10±0.02), penis(0.15±0.03), thymus(0.12±0.03)were lower than that of control group. In the way of intramuscular injection, the average intake of high dose group(5.92±2.01)g/(per?d) was lower than control group(8.60±1.33)g/(per?d). The body temperature(34.90±0.22)℃ and the time of swimming in low temperature (34.00±22.41)s of low dose model group were lower than that of control group(36.43±0.91)℃, (67.17±21.93)s, and the coefficient of thymus of two model groups(0.10±0.02),(0.11±0.06)were lower than that of control group. Conclusion Various dose and model establishment methods of Yang deficiency mice have different the time of symptom appearing, the degree of symptom and sensitive index.
ABSTRACT
Cancer stem cells (CSCs) are thought to drive uncontrolled tumor growth, and the existence of CSCs has recently been proven by direct experimental evidence, including tracing cell lineages within a growing tumor. However, CSCs must be analyzed in additional cancer types. Cancer stem cell-like cells (CSCLCs) are a good alternative system for the study of CSCs, which hold great promise for clinical applications. OCT4, NANOG, and SOX2 are three basic transcription factors that are expressed in both CSCLCs and embryonic stem cells (ESCs). These transcription factors play critical roles in maintaining the pluripotence and self-renewal characteristics of CSCLCs and ESCs. In this review, we discuss the aberrant expression, isoforms, and pseudogenes of OCT4, NANOG, and SOX2 in the CSCLC niche, which contribute to the major differences between CSCLCs and ESCs. We also highlight an anticancer therapy that involves killing specific cancer cells directly by repressing the expression of OCT4, NANOG, or SOX2. Importantly, OCT4, NANOG, and SOX2 provide great promise for clinical applications because reducing their expression or blocking the pathways in which they function may inhibit tumor growth and turn-off the cancer "switch." In the future, a clear understanding of transcription factor regulation will be essential for elucidating the roles of OCT4, NANOG, and SOX2 in tumorigenesis, as well as exploring their use for diagnostic and therapeutic purposes.