The world’s concern about the impacts of tobacco smoke and environmental pollutants on lung health has prompted researchers to seek natural remedies with protective effects. A new study investigates the potential of Vitis vinifera L. var. King Ruby, commonly known for its grapes, as a source of phytochemicals capable of safeguarding lung tissues from the damaging effects of benzo(a)pyrene (B(a)P), a harmful compound found primarily in cigarette smoke.
Research has long highlighted smoking as one of the leading causes of chronic obstructive pulmonary disease (COPD) and lung cancer, with the World Health Organization estimating tobacco use results in approximately 7 million deaths each year. The prominent carcinogen B(a)P is recognized for its role in provoking pulmonary inflammation and cellular damage, leading to increased cancer risk.
To explore this herbal approach, researchers focused on the leaves of the King Ruby variety of grapes, which have demonstrated various beneficial effects through traditional medicine remedies across regions. Utilizing advanced liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), the study identified dozens of potent phytochemicals within the methanol extract of grape leaves, including flavonoids such as quercetin-3-O-β-D-glucuronide and kaempferol-3-O-glucoside.
The study’s investigators applied these extracts to lab-grown cancer cells and mice, aiming to evaluate their protective efficacy against B(a)P-induced lung injury. Findings revealed significant variations in lung protection, particularly at higher concentrations (300 mg/kg) of the extract and its methylene chloride fraction (MCF), which was noted for its ability to minimize cell death and inflammation.
Sulforhodamine B (SRB) assays indicated the MCF showed the most formidable cytotoxic activity against A-549, the human lung cancer cell line, boasting cell viability at just 4.54%. This heightened response led to substantial increases in the antioxidants glutathione (GSH) and notable reductions of malondialdehyde (MDA) levels, which are indicative measures of oxidative stress and cell damage.
The researchers observed significant improvements using histopathological methods, with the lung tissue samples from pre-treated mice exhibiting reduced inflammation and structural damage. Further analysis revealed downregulation of key pro-inflammatory proteins such as cyclooxygenase-2 (COX-2) and the transcription factor nuclear factor-kappa B (NF-κB), both known markers involved in inflammatory responses. Following treatments, the expression levels of these indicators were considerably lower compared to untreated groups exposed to B(a)P alone.
"The histopathological and immunohistochemical improvements observed support the underlying mechanisms of the potential lung protective effect of Vitis vinifera L.," noted the authors. They stress the need for more extensive pre-clinical and clinical investigations to validate the therapeutic potential of these findings.
This research not only sheds light on the protective benefits of grape leaf extracts against environmental toxins but also highlights the possible development of natural pharmacological agents derived from Vitis vinifera L. var. King Ruby, paving the way for novel treatments targeting chemically-induced lung injuries.