Curcumin hybrid molecules for the treatment of Alzheimer's disease: Structure and pharmacological activities.

Alzheimer's disease (AD) is the most common neurodegenerative disease among the elderly. Contemporary treatments can only relieve symptoms but fail to delay disease progression. Curcumin is a naturally derived compound that has demonstrated significant therapeutic effects in AD treatment. Recently, molecular hybridization has been utilized to combine the pharmacophoric groups present in curcumin with those of other AD drugs, resulting in a series of novel compounds that enhance the therapeutic efficacy through multiple mechanisms. In this review, we firstly provide a concise summary of various pathogenetic hypotheses of AD and the mechanism of action of curcumin in AD, as well as the concept of molecular hybridization. Subsequently, we focus on the recent development of hybrid molecules derived from curcumin, summarizing their structures and pharmacological activities, including cholinesterase inhibitory activity, Aß aggregation inhibitory activity, antioxidant activity, and other activities. The structure-activity relationships were further discussed.

Umbilical Cord Blood-Derived Exosomes From Very Preterm Infants With Bronchopulmonary Dysplasia Impaired Endothelial Angiogenesis: Roles of Exosomal MicroRNAs.

Premature infants have a high risk of bronchopulmonary dysplasia (BPD), which is characterized by abnormal development of alveoli and pulmonary vessels. Exosomes and exosomal miRNAs (EXO-miRNAs) from bronchoalveolar lavage fluid are involved in the development of BPD and might serve as predictive biomarkers for BPD. However, the roles of exosomes and EXO-miRNAs from umbilical cord blood of BPD infants in regulating angiogenesis are yet to be elucidated. In this study, we showed that umbilical cord blood-derived exosomes from BPD infants impaired angiogenesis in vitro. Next-generation sequencing of EXO-miRNAs from preterm infants without (NBPD group) or with BPD (BPD group) uncovered a total of 418 differentially expressed (DE) EXO-miRNAs. These DE EXO-miRNAs were primarily enriched in cellular function-associated pathways including the PI3K/Akt and angiogenesis-related signaling pathways. Among those EXO-miRNAs which are associated with PI3K/Akt and angiogenesis-related signaling pathways, BPD reduced the expression of hsa-miR-103a-3p and hsa-miR-185-5p exhibiting the most significant reduction (14.3% and 23.1% of NBPD group, respectively); BPD increased hsa-miR-200a-3p expression by 2.64 folds of the NBPD group. Furthermore, overexpression of hsa-miR-103a-3p and hsa-miR-185-5p in normal human umbilical vein endothelial cells (HUVECs) significantly enhanced endothelial cell proliferation, tube formation, and cell migration, whereas overexpressing hsa-miR-200a-3p inhibited these cellular responses. This study demonstrates that exosomes derived from umbilical cord blood of BPD infants impair angiogenesis, possibly via DE EXO-miRNAs, which might contribute to the development of BPD.

[Angelica Polysaccharide Resists Platelets Apoptosis Induced by LY294002].

OBJECTIVE: To investigate the anti-apoptotic effect of Angelica polysaccharide (APS) on cryopreservated platelets and its mechanism. METHODS: The platelets were divided into 4 group: control group(4 ℃ stored platelets),APS group (APS-treated platelets stored at 4 ℃), LY294002 group (LY294002-treated platelets stored at 4 ℃) and LY294002+APS group(LY294002+APS treated platelets stored at 4 ℃ ). The expression of platelet membrane glycoprotein CD41 and CD61, as well as the platelet apoptotic rate, Caspase 3 expression and mitochondrial membrane potential (MMP) were detected by flow cytometry; the anti-apoptotic mechanism of APS by PI3K /AKT signaling pathway was analyzed by Western blot assay. RESULTS: The apoptosis rate of platelets in LY294002 group obviously increased, the activity of CD41 and CD61 expression gradually decreased along with the enhancement of LY294002 concentrations (r=-0.953)； compared with control group, the apoptosis rate of platelets in LY294002 group was enhanced significantly(P<0.05)，while the apoptosis rate of platelets in LY294002+APS group significantly was reduced(P<0.05) as compare with LY294002 group, which suggest that APS has an anti-apoptotic effect on the cryopreserved platelets. APS decreased the expression of Caspase-3 and inhibited the reduction of mitochondrial membrane potential induced by LY294002, moreover, APS could increase the activation of PI3K /AKT pathway in Plt. CONCLUSION: APS has an anti-apoptotic effect on the cryopreserved platelets through activating the PI3K /AKT pathway, decreasing the expression of apoptosis protease Caspase-3 and inhibiting the reduction of MMP.

Rapid detection of avian influenza virus a and subtype H5N1 by single step multiplex reverse transcription-polymerase chain reaction.

Outbreaks of H5N1 highly pathogenic avian influenza (HPAI) virus caused great economic losses to the poultry industry and resulted in human deaths in Thailand and Viet Nam in 2004. Rapid typing and subtyping of H5N1 viruses, especially from clinical specimens, are desirable for taking prompt control measures to prevent the spread of the disease. Here, we developed a set of oligonucleotide primers able to detect, type and subtype H5 and N1 influenza viruses in a single step multiplex reverse transcription-polymerase chain reaction (RT-PCR). RNA was extracted from allantoic fluid or from specimens with guanidinium isothiocyanate reagent. Reverse transcription and PCR were carried out with a mixture of primers specific for influenza viruses of type A, subtype H5 and N1 in a single reaction system under identical conditions. The amplified DNA fragments were analyzed by agarose gel electrophoresis. All the H5N1 viruses tested in the study and the experimental specimens presented three specific bands by the method established here. The results presented here suggest that the method described below is rapid and specific and, therefore, could be valuable in the rapid detection of H5N1 influenza viruses in clinics.

Genetic analysis of the nonstructural (NS) genes of H9N2 chicken influenza viruses isolated in China during 1998-2002.

H9N2 subtype avian influenza viruses are widespread in domestic poultry. Genetic analysis indicated that three lineages of H9N2 viruses have been established in Eurasia and only one lineage is present on chicken farms in mainland China. Here, NS1 genes of eight H9N2 chicken influenza viruses, isolated in mainland China during 1998-2002, were completely sequenced and phylogenetically analyzed. By comparison, the homology of the NS1 of the A/chicken/Neimenggu/ZH/02 (Ck/NM/ZH/02) strain had a high identity (93.8%) with that of A/chicken/Korea/323/96 (Ck/Kor/323/96), which is an A/duck/Hong Kong/Y439/97 (Dk/HK/Y439/97)-like virus. NS1 peptides of seven strains possessed 217 amino acids, while that of the strain Ck/NM/ZH/02 coded 230 amino acids. Except for the amino acid at position 225, the additional amino acid sequence (13 AAs) of NS1 of Ck/NM/Zh/02 at the carboxy-terminus is identical with that of Ck/Kor/323/96. Phylogenetic analysis showed that seven of the tested strains belong to the A/duck/Hong Kong/Y280/97 (DK/HK/Y280/97)-like lineage, while the NS1 gene of Ck/NM/Zh/02 belongs to the Dk/HK/Y439/97-like lineage and has a close relationship with that of the Ck/Kor/323/96-like viruses. Therefore, although most of the H9N2 influenza viruses circulating on chicken farms in mainland China belong to the DK/HK/Y280/97-like lineage, the present results indicate that the other two of the three H9N2 lineage viruses also circulate in the chicken population in mainland China.