Ting, A. C. J. | bioRxiv Science

bioRxiv2021

16S rRNA Amplicon Sequencing of Bagworm Metisa plana Walker (Lepidoptera: Psychidae)

The bagworm Metisa plana is one of the major pests in the oil palm plantation in Malaysia, with infestation that results in huge economical loss. Currently, the exact cause of the infestation is still undetermined. Studying the bacterial community of M. plana could provide insight on the problem as the bacteria associated with insects often provide numerous benefits to the insect itself. Using 16S rRNA amplicon sequencing, the study was conducted to compare the composition of the bacterial communities of two larval stages (early instar stage and late instar stage) from outbreak area, as well as comparing the late instar stage larvae from non-outbreak and outbreak areas. Generally, the bacterial community was dominated by Proteobacteria and Actinobacteria phyla while the Enterobacteriaceae was found to be the dominant family. When comparing between the early and late instar stage, Proteobacteria phylum was found to be more abundant in the late instar stage (82.36%) than in the early instar stage (82.28%). At the family level, the Enterobacteriaceae was slightly more abundant in late instar stage (75.46%) than in early instar stage (75.29%). The instar stage was observed to have no significant impact on the bacterial variability and showed similar bacterial community structure. When comparing between the non-outbreak area and outbreak, Proteobacteria was significantly more abundant in the outbreak area (82.02%) than in the non-outbreak area (20.57%). However, Actinobacteria was significantly more abundant in the non-outbreak area (76.29%) than in the outbreak area (14.16%). At the family level, Enterobacteriaceae was more abundant in outbreak area (75.41%) than in non-outbreak area (11.67%). Microbacteriaceae was observed to be more abundant in the non-outbreak area (70.87%) than in the outbreak area (12.47%). Although the result showed no significant difference in bacterial variability between different areas, it the bacterial community structure was significantly different.

microbiology↗

bioRxiv2020

Alleviatory effects of Danshen, Salvianolic acid A and Salvianolic acid B on PC12 neuronal cells and Drosophila melanogaster model of Alzheimer's disease.

Alzheimers disease (AD) is the most common form of neurodegenerative disorder worldwide. Its pathogenesis involves the hallmark aggregation of amyloid-beta (A{beta}). Of all the A{beta} oligomers formed in the brain, A{beta}42 has been found to be the most toxic and aggressive. Despite this, the mechanism behind this disease remains elusive. With the ability to utilize various genetic manipulations, Drosophila melanogaster is ideal in analysing not only cellular characteristics, but also physiological and behavioural traits of human neurodegenerative diseases. Danshen water extract (DWE), obtained from the root of Salvia miltiorrhiza Bunge, was found to have a vast array of beneficial properties. In this study, DWE, and its major components, Salvianolic acid A (SalA) and Salvianolic acid B (SalB) were tested for their abilities to ameliorate A{beta}42s effects. DWE, SalA and SalB were confirmed to be able to reduce fibrillation of A{beta}42. As A{beta}42 causes neurodegeneration on neurons, DWE, SalA and SalB were tested on A{beta}42-treated PC12 neuronal cells and were shown to increase cell viability. DWE and its components were then tested on the Drosophila melanogaster AD model and their rescue effects were further characterized. When human A{beta}42 was expressed, the Drosophila exhibited degenerated eye structures known as the rough eye phenotype (REP), reduced lifespan and deteriorated locomotor ability. Administration of DWE, SalA and SalB partially reverted the REP, increased the age of AD Drosophila and improved most of the mobility of AD Drosophila. In conclusion, DWE and its components may have therapeutic potential for AD patients and possibly other forms of brain diseases.

pharmacology and toxicology↗