Perilipins are evolutionarily conserved from Drosophila to humans, the lipid storage droplet 1 (Lsd1) is a Drosophila homolog of human perilipin 1. The function of Lsd1 as a regulator of lipolysis in Drosophila has been demonstrated, as the Lsd1 mutant causes an increase of lipid droplet size. However, the functions of this gene during development are still under investigation. In order to determine the function of Lsd1 during development, Lsd1 was knocked down in Drosophila using the GAL4-UAS system. Selective knockdown of Lsd1 in the dorsal wing disc caused an atrophied wing phenotype. The generation of reactive oxygen species in the wing pouch compartment of the Lsd1-knockdown flies was significantly higher than in the control. Immunostaining with caspase-3 antibody revealed a greater number of apoptotic cells in Lsd1-knockdown wing discs than in the control. Cell death by autophagy was also induced in the knockdown flies. Moreover, cells deprived of Lsd1 showed mitochondrial expansion and decreased ATP levels. These results strongly suggest that knockdown of Lsd1 induces mitochondrial stress and the production of reactive oxygen species that result in cell death, via apoptosis and the autophagy pathway. These results highlight the roles of Drosophila Lsd1 during wing development.

Background: The spread of drug resistance in malaria parasites and the limited number of effective drugs for treatment indicates the need for new anti-malarial compounds. Current assays evaluating drugs against Plasmodium falciparum require expensive materials and equipment, thus limiting the search for new drugs, particularly in developing countries. This study describes an inexpensive procedure that is based on the advantage of a positive correlation between the haemozoin level of infected erythrocytes and parasite load. Methods: The relationship between parasitaemia and the haemozoin level of infected erythrocytes was investigated after converting haemozoin into monomeric haem. The 50% inhibitory concentration (IC₅₀) values of chloroquine, quinine, artemisinin, quinidine and clotrimazole against P. falciparum K1 and 9A strains were determined using the novel assay method. Results: The haemozoin of parasites was extracted and converted into monomeric haem, allowing the use of a colorimeter to efficiently and rapidly measure the growth of the parasites. There was a strong and direct linear relationship between the absorbance of haem converted from haemozoin and the percentage of the parasite (R² = 0.9929). Furthermore, the IC₅₀ values of drugs were within the range of the values previously reported. Conclusion: The haemozoin-based colorimetric assay can be considered as an alternative, simple, robust, inexpensive and convenient method, making it applicable in developing countries.

Chau Thanh Tuan and Tran Thanh Men. J. Microbiol. Biotechnol. 2024;34:1-10. https://doi.org/10.4014/jmb.2406.06025

Brown algae (Dictyopteris polypodioides) extract (DP) presented high inhibitory potential against α-amylase. The present study aims to isolate, purify and evaluate the antihyperglycemic and anti-type 2 diabetic activities of marine hydroquinone from DP. Marine hydroquinones were isolated using silica gel, HPLC, and NMR spectroscopy was used to identify compound 1 and compound 2 as zonarol and isozonarol, respectively. The anti-hyperglycemic and anti-type 2 diabetic activities of zonarol were investigated by in vitro assay (α-amylase, α-glucosidase), Lineweaver–Burk plot and Type 2 diabetes mellitus model (T2DM) mice induced by streptozotocin (STZ). Zonarol had the highest content and the strongest inhibitory activity against α-glucosidase (IC₅₀ value of 6.03 mg L⁻¹) and α-amylase (IC₅₀ value of 19.29 mg L⁻¹) in a competitive inhibition and mix-type manner, respectively. The maltose and starch loading tests revealed that zonarol significantly reduced postprandial glycemia after 30 min loading (9.12 and 8.12 mg/dL, respectively), compared to normal (11.37 and 12.37 mg/dL, respectively). Zonarol exhibited pancreatic islet cell rejuvenation, as evidenced by increased pancreatic islet mass, and hence helps in the restoration of insulin levels and therefore improves the glucose metabolism in STZ-induced diabetic mice. Zonarol treatment in T2DM elevated abundant levels of main SCFAs (propionate, butyrate, and valeric acid), which are closely related to glucose metabolism homeostasis. Our finding indicates that zonarol could be used as a food supplement to treat hyperglycemia and diabetes.