Extracts of pine bark (Pinus sylvestris) inhibit Cryptosporidium parvum growth in cell culture

Abstract

The widespread apicomplexan parasite Cryptosporidium parvum is responsible for severe gastrointestinal disease in humans and animals. The treatment options are limited, and the efficacy of available drugs is low. Bark contains condensed tannins (CT), which are bioactive compounds previously shown to inhibit parasite development. Here, we examined the anti-cryptosporidial properties of bark extract of Scots pine (Pinus sylvestris) against C. parvum by means of an in vitro growth inhibition test. We hypothesised that bark extracts would have dose-dependent inhibitory effects on the development of C. parvum in cell culture.Bark extracts from Scots pine extracted with acetone, methanol, and water as solvents were investigated using human colorectal adenocarcinoma cells infected with C. parvum. Oocysts were inoculated onto the cell monolayer and bark extract was added at seven different concentrations. Parasite growth inhibition was quantified by qPCR.The acetone and methanol extracts demonstrated a sigmoid dose-dependent inhibition of C. parvum. The IC50 values were 244.6 and 279.1 µg dry matter extract/mL, and 25.4 and 24.1 µg CT/mL, for acetone and methanol extracts, respectively. The IC50 for both extracts were similar, both with regard to the dry matter concentration of each extract and to CT concentrations.Given the limited treatment options available for Cryptosporidium spp., the evidence generated in our study encourages further investigation into the in vitro and in vivo effects of pine bark extracts against C. parvum.

Silver Nanoparticles Synthesized from Abies alba and Pinus sylvestris Bark Extracts: Characterization, Antioxidant, Cytotoxic, and Antibacterial Effects

“…Previous investigations on A. alba bark extracts in cell-free and cell-based assays revealed antioxidant (free radical scavenging activity, decrease of the production of reactive oxygen species, reduction of lipoprotein oxidation) [ 22 , 23 , 24 ], antisteatotic (decrease of lipid and cholesterol accumulation in hepatocytes, slight induction of cholesterol conversion to bile acids), and antihypertensive (inhibition of angiotensin-converting enzyme) effects [ 24 ]. P. sylvestris bark extracts were reported to display anti-inflammatory activity (reduction of the synthesis of pro-inflammatory prostaglandin E 2 and nitric oxide) in murine macrophages [ 25 ], pro-apoptotic effects in human cervical adenocarcinoma (HeLa) cells [ 21 ], antiparasitic activity against Cryptosporidium parvum , responsible for severe diarrhoeal disease [ 26 ], antibacterial activity against S. aureus , including a methicillin-resistant strain, and free radical scavenging activity [ 27 ]. To the best of our knowledge, there is no report on the phytosynthesis of AgNPs from A. alba or P. sylvestris bark extracts.…”

Condensed tannins, novel compounds and sources of variation determine the antiparasitic activity of Nordic conifer bark against gastrointestinal nematodes

“…For preparation of the bark extracts, the bark was milled, and extracts were produced as described by 16 using three different solvents: water, 70% acetone in water (Ace-Wa), and 80% methanol in water (Met-Wa). This produced three different extracts from each of the six bark batches mentioned above and included in the bark code with the addition of -water, -acetone and -methanol.…”

The Influence of Ecological Factors on the Phytochemical Characteristics of Pinus cembra L.

“…There are data from the literature that demonstrate the cytotoxicity of some extracts obtained from the bark of different pine species [7][8][9]. Cytotoxic activity was also observed in hydromethanolic extracts obtained from Pinus cembra L. needles when testing their inhibition level on the HeLa cell line (human cervix cancer cell line).…”