Polyalthia Longifolia Induced Apoptosis via miR-484 Downregulation: A Multimodal In Situ Microscopy, In Vitro, and In...

Area of Science:

• Natural Product Chemistry
• Molecular Biology
• Cancer Research

Background:

• Polyalthia longifolia (PL) is a potential source of anticancer agents.
• The precise microstructural mechanisms of PL's anticancer activity, particularly involving microRNA-484 (miR-484), require further elucidation.

Purpose of the Study:

• To investigate the role of miR-484 in Polyalthia longifolia methanolic leaf extract (PLME)-induced apoptosis in HeLa cells.
• To elucidate the microstructural mechanisms of PLME's anticancer activity using a multimodal approach.

Main Methods:

• In situ microscopy (SEM) for visualizing cellular morphology.
• In vitro assays (MTT, caspase-3 activity) to assess cell viability and apoptosis.
• In vivo xenograft models to evaluate tumor suppression.
• miR-484 overexpression and downregulation experiments.
• Quantitative real-time PCR (qRT-PCR) for gene expression analysis.

Main Results:

• PLME significantly reduced miR-484 expression and induced apoptotic morphology in HeLa cells.
• Overexpression of miR-484 counteracted PLME-induced apoptosis, preserving cell viability and proliferation markers.
• PLME demonstrated significant tumor suppression in vivo, which was partially reversed by miR-484 overexpression.
• A consistent inverse correlation between PLME exposure and miR-484 levels was observed across in vitro and in vivo models.

Conclusions:

• PLME induces apoptosis in cancer cells primarily through the downregulation of miR-484.
• Multimodal microscopy provides critical in situ evidence for understanding natural product-induced cellular changes.
• This study validates the therapeutic potential of P. longifolia and highlights the importance of miR-484 in its anticancer mechanism.