Neuroprotective Effects of Leptin on the APP/PS1 Alzheimer's Disease Mouse Model: Role of Microglial and Neuroinflammation

Background

Microglia are closely linked to Alzheimer's disease (AD) many years ago; however, the pathological mechanisms of AD remain unclear. The purpose of this study was to determine whether leptin affected microglia in the hippocampus of young and aged male APP/PS1 mice.

Objective

In a transgenic model of AD, we investigated the association between intraperitoneal injection of leptin and microglia.

Methods

We intraperitoneal injection of leptin (1mg/kg) every day for one week and analyzed inflammatory markers in microglia in the hippocampus of adult (6 months) and aged (12 months) APP/PS1 mice.

Results

In all leptin treatment group, the brain Aβ levels were decrease. We found increased levels of IL-1β, IL-6 and microglial activation in the hippocampus of adult mice. Using aged mice as an experimental model for chronic neuroinflammation and leptin resistance, the number of Iba-1+ microglia and the levels of IL-1β/IL-6 in the hippocampus were greatly increased as compared to the adult. But between the leptin treatment and un-treatment, there were no difference.

Conclusion

Leptin signaling would regulate the activation of microglia and the release of inflammatory factors, but it is not the only underlying mechanism in the neuroprotective effects of AD pathogenesis.

Octahedral Distortion and Displacement-Type Ferroelectricity with Switchable Photovoltaic Effect in a 3d^{3}-Electron Perovskite System

Because of the half-filled t_{2g}-electron configuration, the BO_{6} octahedral distortion in a 3d^{3} perovskite system is usually very limited. In this Letter, a perovskitelike oxide Hg_{0.75}Pb_{0.25}MnO_{3} (HPMO) with a 3d^{3} Mn^{4+} state was synthesized by using high pressure and high temperature methods. This compound exhibits an unusually large octahedral distortion enhanced by approximately 2 orders of magnitude compared with that observed in other 3d^{3} perovskite systems like RCr^{3+}O_{3} (R=rare earth). Essentially different from centrosymmetric HgMnO_{3} and PbMnO_{3}, the A-site doped HPMO presents a polar crystal structure with the space group Ama2 and a substantial spontaneous electric polarization (26.5  μC/cm^{2} in theory) arising from the off-center displacements of A- and B-site ions. More interestingly, a prominent net photocurrent and switchable photovoltaic effect with a sustainable photoresponse were observed in the current polycrystalline HPMO. This Letter provides an exceptional d^{3} material system which shows unusually large octahedral distortion and displacement-type ferroelectricity violating the "d^{0}-ness" rule.

[Energy metabolism characteristic with risk of secondary bacterial infection in patients with hepatitis B virus-related chronic liver disease]

Objective: To investigate and analyze the energy metabolism characteristics and the correlation between energy metabolism and the risk of secondary bacterial infection in patients with hepatitis B virus-related chronic liver disease (HBV-CLD). Methods: Data of 183 cases admitted to the Mengchao Hepatobiliary Hospital of Fujian Medical University from November 2017 to November 2020 were retrospectively analyzed. 79 cases of chronic hepatitis B, 51 cases of hepatitis B-related liver cirrhosis, and 53 cases of hepatitis B-related liver failure were collected. Among them patients with liver failure and decompensated liver cirrhosis were defined as severe liver disease group. The Quark RMR indirect calorimetry (COSMED Corporation, Italy) was used to exam the patients' energy metabolism condition, and the incidences of secondary bacterial infection of the patients during hospitalization were recorded. Shapiro-Wilk test and normal QQ plot were used to analyze the normal distribution of continuous variable data, which was consistent with the normal distribution and was described by mean ± standard deviation. In addition, if it did not conform to the normal distribution, the median and interquartile distance were used to describe it. Levene's test was used to test the homogeneity of variance of the data, which was consistent with the normal distribution. The t-test was used to compare the means of the two groups of samples. One-way analysis of variance was used to compare the mean values of the three groups of samples, and then the Tukey's test was used to compare the two groups. If the variance was uneven or did not conform to the normal distribution, the Wilcoxon rank sum test was used to compare the differences between the two groups. Kruskal-Wallis test (H test) was used to compare the differences between the three groups of samples, and then the Dunnett's test (Z test) was used for comparison between the two groups. Categorical variable data were analyzed using chi-square test. Logistic regression analysis was used to screen independent risk factors, and the criteria for variable inclusion (P < 0.05). Results: The respiratory entropy (RQ) and non-protein respiratory entropy (npRQ) of the three groups had statistically significant difference (P < 0.05). Among them, the RQ and npRQ of the chronic hepatitis B group were higher than hepatitis B-related liver cirrhosis group and hepatitis B-related liver failure group. There were statistically significant differences in fat oxidation rate (FAT%) and carbohydrate oxidation rate (CHO%) between the three groups (P < 0.05). Compared with hepatitis B-related liver cirrhosis group and hepatitis B-related liver failure group, chronic hepatitis B group (P < 0.05) had lower FAT% and higher CHO%. There were no statistically significant differences in the measured and predicted resting energy expenditure and protein oxidation rate (PRO%) between the three groups. The incidence of secondary bacterial infection in patients with severe liver disease was 48.39% (45/93). Compared with the non-infected group, the RQ and npRQ values ​​of the infected group were significantly decreased (P < 0.05), while FAT% was significantly increased (P < 0.05). Logistic regression analysis showed that glutamyltransferase, cholesterol, and npRQ were independent risk factors for secondary bacterial infections in patients with severe liver disease. Glutamyltransferase elevation, and cholesterol and npRQ depletion had suggested an increased risk of secondary bacterial infection. Subgroup analysis of patients with hepatitis B-related liver failure also showed that compared with non-infected group, RQ value and npRQ value of secondary bacterial infection group were significantly decreased (P < 0.05), while FAT% was significantly increased (P < 0.05). Conclusion: Patients with hepatitis B virus-related chronic liver disease generally have abnormal energy metabolism. Low RQ, npRQ, CHO% and high FAT% are related to the severity of the disease; while npRQ reduction is related to the risk of secondary bacterial infection in patients with severe liver disease, and thus can be used as a clinical prognostic indicator.

[Establishment of nutrition literacy core items for Chinese people]

Objective: To establish core items of nutrition literacy for general population in China. Methods: The framework system and preliminary items of nutrition literacy were established through literature review and experts' consultation. Content validity test was used to determine the nutrition literacy item. Thirteen experts in the field of human nutrition, health education and nutrition and diseases were invited to score the importance of each nutrition literacy item via Email. The judgment basis and familiarity of experts towards the items, active coefficient, and content validity were analyzed to generate the final list of nutrition literacy items. Results: 92.3% of questionnaires in two rounds were collected.The active coefficient of experts was satisfied and the authority coefficient was 0.96.In the content validity evaluation, the correlation I-CVI value of each item was above 0.83 and the κ value was above 0.74. The evaluation result was excellent.After the second round of expert consultation, all selected items met the inclusion criteria. We identified the final list of nutrition literacy items consisting of three scales (knowledge and concepts, lifestyles and dietary behaviors, and basic skills), ten subscales (basic nutrition philosophy, food classification and nutrition knowledge, healthy weight, eating behavior and culture, balanced diet, exercise health, food assessment, nutrition information acquisition and decision, nutrition safety, and weight management)with 25 items in total. Conclusions: The framework system and core items of nutrition literacy are established for Chinese people based on the content validity evaluation. The experts involved in the consultation process present a performance with good representativeness, enthusiasm and authority, and the content validity evaluation result is satisfied.

[Establishment of nutrition literacy core items for Chinese old people]

Objective: To establish the nutrition literacy core items for older people in China. Methods: The framework system and preliminary items of nutrition literacy were established through literature review and experts consultation. Content validity test was used to determine the nutrition literacy items. Seven experts in the field of human nutrition, health education and nutrition and diseases were invited to score the importance of each nutrition literacy item via Email. The judgment basis and familiarity of expertstowards the items, active coefficient, and content validitywere evaluated and analyzed to generate the final list of nutritionliteracy items. Results: A total of 85.7% (6/7) of questionnaires in two rounds were collected.The active coefficient of experts was satisfied and the authority coefficient was 0.96. In the content validity evaluation, the correlation I-CVI value of each item was above 0.90 and theκvalue was above 0.74. The evaluation result was excellent. After the second round of consultation, all selected items met the inclusion criteria. We identified the final list of nutrition literacy items consisting of three scales (knowledge and concepts, lifestyles and dietary behaviors, and basic skills), twelve subscales (reasonable nutrition, healthy weight, environment of dining, food classification, nutrition and disease, eat regularly, balanced diet, exercise health, information getting, household food measurement, reading nutrition label and calculating, and food safety)with 20 items in total. Conclusions: The framework system and core items of nutrition literacy are established for Chinese older people based on the content validity evaluation. The experts involved in the consultation process present a performance with good representativeness, enthusiasm and authority, and the content validity evaluation result is satisfied.

Spin-Canting-Induced Band Reconstruction in the Dirac Material Ca_{1-x}Na_{x}MnBi_{2}

The ternary AMnBi_{2} (A is alkaline as well as rare-earth atom) materials provide an arena for investigating the interplay between low-dimensional magnetism of the antiferromagnetic MnBi layers and the electronic states in the intercalated Bi layers, which harbor relativistic fermions. Here, we report on a comprehensive study of the optical properties and magnetic torque response of Ca_{1-x}Na_{x}MnBi_{2}. Our findings give evidence for a spin canting occurring at T_{s}∼50-100  K. With the support of first-principles calculations we establish a direct link between the spin canting and the reconstruction of the electronic band structure, having immediate implications for the spectral weight reshuffling in the optical response, signaling a partial gapping of the Fermi surface, and the dc transport properties below T_{s}.

B9-serine residue is crucial for insulin actions in glucose metabolism

AIM

To explore the importance of B9 and B10 amino acid residues in the insulin molecule.

METHODS

The [B9Glu, B10Asp] insulin (E,D-insulin) receptor binding activity, glucose upta ke activity, and lipogenesis activity were measured in isolated adipocytes. The translocation of glucose transporter 4 (Glut4) and the phosphorylation of insulin receptor (IR) stimulated by E, D-insulin were determined by Western blotting.

RESULTS

Compared with native insulin, the receptor binding activity of E,D-insulin was 31 %; the stimulating activity of E,D-insulin in glucose transport and lipogenesis were 45 % and 40 % respectively; the stimulations of Glut4 translocation and insulin receptor autophosphorylation of E,D-insulin were about 58 % and 46 % respectively.

CONCLUSION

B9-serine residue is crucial for insulin actions in glucose metabolism.

Synergistic effects of geldanamycin and antitumor drugs

AIM

To study the effect of geldanamycin (GDM) on cell-cycle of human hepatoma BEL-7402 cells and the antitumor activity of cisplatin and mitomycin C in combination with GDM in vitro and in vivo.

METHODS

MTT assay was used to determine the growth inhibition of hepatoma BEL-7402 cells. Cell cycle was analyzed by flow cytometry. Transplantable murine hepatoma 22 model was used to evaluate the antitumor activity of drugs in vivo.

RESULTS

The IC50 value of GDM for hepatoma BEL-7402 cells by MTT assay was found to be 0.28 mumol.L-1. At concentrations of 0.1, 1.0, and 10 mumol.L-1, GDM reduced the proportion of S phase and induced G2/M arrest in BEL-7402 cells. At relatively low cytotoxic concentration, 0.1 or 0.2 mumol.L-1, GDM markedly potentiated the cytotoxicity of a series of chemotherapeutic agents including cisplatin, mitomycin C, adriamycin and cytarabine against BEL-7402 cells. The inhibition of tumor growth by cisplatin and mitomycin C was also enhanced in transplantable hepatoma 22-bearing mice when these agents were administered in combination with GDM 0.38 mg.kg-1. The synergistic effects were very significant with CDI < 0.7.

CONCLUSION

These results suggest that GDM, as a biochemical modulator targeting Hsp90 function, may be potentially useful in cancer chemotherapy.

Tuberculosis versus lymphomas in the abdominal lymph nodes: evaluation with contrast-enhanced CT

OBJECTIVE

Tuberculosis in the abdominal lymph nodes may be difficult to distinguish from lymphomas. This study evaluated specific CT imaging criteria for differentiating these entities.

MATERIALS AND METHODS

We retrospectively reviewed the anatomic distribution and CT enhancement patterns of disease in 69 patients, 26 (38%) with tuberculosis and 43 (62%) with untreated lymphomas involving abdominal lymph nodes. Of the patients with tuberculosis, five (19%) had disseminated disease and 21 (81%) had nondisseminated disease. Of the patients with lymphomas, 16 (37%) had Hodgkin's disease and 27 (63%) had non-Hodgkin's lymphoma.

RESULTS

Disseminated and nondisseminated tuberculosis involved predominantly lesser omental, mesenteric, anterior pararenal, and upper paraaortic lymph nodes. Lower paraaortic lymph nodes were involved more often in Hodgkin's disease (15 patients [94%]), non-Hodgkin's lymphoma (24 patients [89%]), and disseminated tuberculosis (five patients [100%]) than in nondisseminated tuberculosis (one patient [5%]). Mesenteric lymph nodes were involved more often in disseminated tuberculosis (four patients [80%]) and nondisseminated tuberculosis (11 patients [52%]) than in Hodgkin's disease (one patient [6%]) (p < .01). Anatomic distribution was not different between disseminated tuberculosis and non-Hodgkin's lymphoma. Tuberculous lymphadenopathy commonly showed peripheral enhancement, frequently with a multilocular appearance, whereas lymphomatous adenopathy characteristically showed homogeneous attenuation (14 patients [87.5%] with Hodgkin's disease and 19 patients [70%] with non-Hodgkin's lymphoma [p < .01]).

CONCLUSION

Our findings indicate that the anatomic distribution and specific enhancement patterns of lymphadenopathy seen on contrast-enhanced CT can be useful in differentiating between tuberculosis and untreated lymphomas of the abdominal lymph nodes.