Calcium carbonate-enriched Cucurbita maxima increases the relative expression level of the PCSK9 gene in the liver of ovariectomized rats

This study aimed to determine the effect of pumpkin (Cucurbita maxima) enriched with calcium carbonate on the PCSK9 gene relative expression level in an animal model of postmenopausal osteoporosis. The study was conducted in forty female Wistar rats, which were divided into five groups: a group fed a standard diet (C) and four ovariectomized groups fed a standard diet (OVX_C): a group receiving a calcium-free diet (OVX_DEF), a group receiving a calcium-deficient diet with the addition of unenriched C.maxima (OVX_P), and the OVX_PCaC group that was fed a diet with the addition of C. maxima enriched with calcium carbonate. After 12 weeks of the dietary intervention, the rats were sacrificed, and their tissues and blood were collected. Serum levels of inflammatory markers, antioxidants, and lipids were measured using enzyme-linked immunosorbent assay method. The PCSK9 gene relative expression level was assessed using quantitative PCR. It was found that ovariectomy decreased PCSK9 gene expression. Enriched C. maxima, particularly with calcium carbonate, increased PCSK9 expression above control levels. LDL and HDL cholesterol concentrations were affected by ovariectomy but not by diet modifications. A significant increase in serum C-reactive protein was observed after consuming unenriched C. maxima, as opposed to C. maxima enriched with calcium. However, after consuming both types of C. maxima, the concentration of cyclooxygenase 2 and lipoxygenase 1 in the serum decreased. These findings indicate that calcium-enriched C. maxima modulates PCSK9 expression, inflammation, and lipid metabolism, offering potential benefits in managing estrogen deficiency-related metabolic disturbances.