Pro‑differentiating compounds for human intervertebral disc cells are present in Violina pumpkin leaf extracts

Abstract

Intervertebral disc (IVd) degeneration (Idd) is closely associated with inflammation, oxidative stress and loss of the discogenic phenotype, which current therapies are unable to reverse. In the present study, the effects of acetone extract from Violina pumpkin (Cucurbita moschata) leaves on degenerated IVd cells were investigated. IVd cells were isolated from the degenerated disc tissue of patients undergoing spinal surgery and were exposed to acetone extract and three major thin layer chromatography subfractions. The results revealed that, in particular, the cells benefited from exposure to subfraction Fr7, which consisted almost entirely of p-Coumaric acid. Western blot and immunocytochemical analysis showed that Fr7 induced a significant increase in discogenic transcription factors (SOX9 and tricho-rhino-phalangeal syndrome type I protein, zinc finger protein), extracellular matrix components (aggrecan, collagen type II), cellular homeostasis and stress response regulators, such as FOXO3a, nuclear factor erythroid 2-related factor 2, superoxide dismutase 2 and sirtuin 1. Two important markers related to the presence and activity of stem cells, migratory capacity and OCT4 expression, were assessed by scratch assay and western blotting, respectively, and were significantly increased in Fr7-treated cells. Moreover, Fr7 counteracted H 2 O 2 -triggered cell damage, preventing increases in the pro-inflammatory and anti-chondrogenic microRNA (miR), miR-221. These findings strengthen the hypothesis that adequate stimuli can support resident cells to repopulate the degenerated IVd and restart the anabolic machinery. Taken together, these data contribute to the discovery of molecules potentially effective in slowing the progression of Idd, a disease for which there is currently no effective treatment. Moreover, the use of part of a plant, the pumpkin leaves, which is usually considered a waste product in the Western world, indicated that it contains substances with potential beneficial effects on human health.

Plant-Derived Senotherapeutics for the Prevention and Treatment of Intervertebral Disc Degeneration and Aging

“…In accordance with its chondroprotective role, p-coumaric acid has been found to mitigate H 2 O 2 -induced senescence traits in human NP IVD cells in vitro, as shown by the decrease of H 2 O 2 -induced SA-β-Gal-positive staining, the decline of H 2 O 2 -induced p16 INK4a , p53, COX-2, iNOS gene expression, the reversal of H 2 O 2 -induced cell cycle arrest and the up-regulation of aggrecan and type II collagen expression [ 47 ]. In favor of the protective effect of p-coumaric acid on IVD cells, a subfraction of an acetone extract from Violina pumpkin ( Cucurbita moschata ) leaves—consisting almost entirely of p-coumaric acid—has been reported to result in the attenuation of H 2 O 2 -induced intracellular ROS levels, the overexpression of SOX9, transcriptional repressor GATA binding 1 (TRPS1) and FOXO3a, the up-regulation of aggrecan and type II collagen, along with the down-regulation of MMP-13 and the elevated expression levels of Nrf2, SIRT1 and SOD2 in degenerated human IVD cells [ 110 ].…”

Effects of Walnut and Pumpkin on Selective Neurophenotypes of Autism Spectrum Disorders: A Case Study

“…Because of differential control by microRNAs (particularly miR-451), there appears to be a decrease in 14-3-3 isoforms, which accounts for the reduced availability of the melatonergic pathway in ASD. Since pumpkin and walnuts both strongly regulate a number of miRNAs [135,136], some of walnuts' effectiveness may be related to how the tryptophan-melatonin pathway is regulated.…”