Aqueous Bark Extract ofCeiba speciosa(A. St.-Hill) Ravenna Protects against Glucose Toxicity inCaenorhabditis elegans

Abstract

Plants are widely used in folk medicine because of their pharmacological properties. Ceiba speciosa, popularly known as paineira-rosa or tree-of-wool, is a species found in the Northwest of Rio Grande do Sul, being native of the upper Uruguay River, Brazil. The tea obtained from the stem bark is employed in folk medicine to reduce cholesterol, triacylglycerides, and glucose levels. However, there are no studies in the literature proving its efficacy or the safety of its use. For this study, we used Caenorhabditis elegans as an animal model considering its advantages for risk assessment and pharmacological screenings. For the toxicological tests, C. elegans N2 (wild type) was treated with the aqueous extract of the stem bark of C. speciosa (ECE) at the first larval stage (L1) at concentrations of 5, 25, 50, and 250 μg/mL. To evaluate biological activities, we challenged the extract for oxidative stress resistance in the presence of paraquat (0.5 mM), H2O2 (1 mM), and against glucose-induced toxicity. Our results demonstrated that ECE did not alter survival rate, pharyngeal pumping, and reproduction of the nematodes. The extract was not able to protect the nematodes against the toxicity induced by prooxidants. Notably, ECE protected against glucotoxicity by increasing worms’ life span and by reducing glucose levels. On the other hand, ECE treatment did not reduce lipid accumulation induced by exogenous glucose feeding, as observed in worms which lipid droplets were tagged with GFP. Based on our results, we believe that the extract is indeed promising for further studies focusing on carbohydrates metabolism; however, it needs to be carefully evaluated since the extract does not seem to modulate lipid accumulation.

Lipid lowering and anti-ageing effects of edible flowers of Viola x wittrockiana Gams in a Caenorhabditis elegans obese model

“…In the C. elegans model, exposure to excess glucose is translated into a faster deterioration of the organism's detoxification mechanisms, mitochondrial dysfunction, increase of the ROS formation and induction of autophagy and it shortens its life span as well as causes impairment of health span and increase of fat accumulation. 58–65 The tested concentrations of the Viola extract reduced the lipid storage in the nematodes in a dose-dependent manner, as shown in Fig. 2B.…”

Genus <i>Ceiba</i> Mill. in Brazil: A comprehensive review on its ethnopharmacology, phytochemistry and bioactivities

“…Bark aqueous extract can increase glucose utilization and regulate insulin levels. These results were observed in protocols with the nematode Caenorhabditis elegans, with reduced body glucose levels and increased longevity of the animals, protecting them against glucotoxicity (Santos et al, 2020). Seed fixed oil has anti-obesity potential, by slightly inhibiting α-amylase, α-glucosidase, and pancreatic lipase enzymes activity, with IC 50 values of 135.69, 158.22 and 127.57 µg/mL, respectively (Rosselli et al, 2020).…”

Pigment of Ceiba speciosa (A. St.-Hil.) Flowers: Separation, Extraction, Purification and Antioxidant Activity

“…Preliminary research suggests that C. speciosa leaf extracts have antioxidant, anti-inflammatory, antipyretic, antibacterial and antifungal functions [ 14 , 15 ], while its seed oil shows hypoglycemic and anti-obesity properties [ 16 ]. An aqueous extract of C. speciosa bark has a low toxicity and the potential to treat hyperglycemia in animals [ 17 ]. However, to date, there has been no investigation of the extraction and possible beneficial functions of the flower pigment of C. speciosa (FPCS).…”