Mitogenic potential of endogenous GlcNAc-specific lectins from rat brain cell nuclear membranes

Lectins are carbohydrate-binding proteins that participate in diverse biological processes, including cell adhesion, immune modulation, cell proliferation. While plant-derived lectins are well characterized for their proliferative effects, these properties of animal-derived lectins, particularly from neural tissues, remain poorly understood. This study aimed to evaluate the proliferative potential of a GlcNAc-specific lectin isolated from the cell nuclear membrane of rat brain cortex cells using the MTT assay.

GlcNAc-specific lectins were purified via affinity chromatography from the cell nuclear membrane protein fraction of rat brain tissue. Human peripheral blood lymphocytes were incubated with the isolated lectins, and metabolic activity was assessed using the MTT colorimetric assay. Absorbance was measured at 540 nm. Statistical analysis was performed using Student's t-test.

Human peripheral blood lymphocytes with GlcNAc-specific lectins exhibiting hemagglutination activity showed a statistically significant, approximately ten times increase in optical density compared to controls (p < 0.05), indicating elevated metabolic activity. Although MTT reduction reflects mitochondrial function rather than direct cell proliferation, this increase suggests a mitogen-like proliferative effect. Remarkably, the GlcNAc-specific lectin continued to induce proliferative activity even having no hemagglutination activity.

These findings suggest that rat brain-derived GlcNAc-specific lectins, which are Ca²⁺, Mg²⁺ glycoproteins may possess proliferative activity, potentially contributing to the regulation of neural cell proliferation or repair. Further studies are warranted to elucidate the underlying mechanisms.