Studies of embryotoxicity and the incidence of external malformations after continuous intravenous infusion of alpha-chaconine in pregnant rats

Is there any association between blood glycoalkaloid levels and anencephaly in human?

AIM

In various experimental animal studies, it has been proven that solanine, a subtype of glycoalkaloids, is responsible for neural tube defects. However, there have not been any human studies yet in this area. Our aim is to investigate whether there are any connections between blood glycoalkaloid levels and anencephaly in humans.

METHODS

Blood and amniotic fluid samples were taken from patients diagnosed with fetal anencephaly during pregnancy. The samples from patients with normal pregnancies were taken as well and was compared to the patients with fetal anencephaly during pregnancy. We searched the levels of three glycoalkaloids: solanine, chaconine and solamargine in the collected samples.

RESULTS

Solanine, which is one of the glycoalkaloids, could not be detected in both serum and amniotic fluid in the anencephaly as well as the control groups. However, alpha-solamargine levels were observed to be significantly higher in the blood and amniotic fluid samples of the control group than in the study group (p = 0.04). Alpha-chaconine levels were also significantly higher in the control group (p < 0.001) as well.

CONCLUSION

Based on our tests, we can conclude that no connections were found between blood solanine levels and anencephaly during pregnancy. Alpha-chaconine and alpha-solamargine levels were observed to be higher in blood and amniotic fluid in pregnancies without anencephaly. The relationship between glycoalkaloids and congenital anomalies needs to be further investigated in tissues other than blood.

α-Solanine Causes Cellular Dysfunction of Human Trophoblast Cells via Apoptosis and Autophagy

The trophoblast, an embryonic tissue, exerts a crucial role in the processes of implantation and placentation. Toxins in food can cause malfunction of trophoblasts, resulting in apoptosis, oxidative stress, and abnormal angiogenesis. α-solanine, a steroidal glycoalkaloid, has antitumor properties on several cancer cells. However, its effect on human trophoblasts has not been elucidated. In this study, human extravillous trophoblast HTR-8/SVneo cells were exposed to α-solanine. Cellular functions including proliferation, migration, invasion, tube formation, and apoptosis were assessed. To monitor autophagic flux, trophoblasts were transfected with a mCherry-GFP-LC3B vector using lentiviral transduction, and expression of autophagy-related biomarkers including Beclin 1, Atgl3, and microtubule-associated protein 1 light chain-3 (MAP1-LC3) were detected. The results show that application of 20 μM α-solanine or above inhibited the cell viability, migration, invasion, and tube formation of the human trophoblast. Cell cycle was arrested at S and G2/M phases in response to 30 μM α-solanine. α-solanine induced apoptosis of HTR-8/SVneo cells and triggered autophagy by increasing the autophagic gene expression and stimulating the formation of autophagosome and autophagic flux. In conclusion, α-solanine can impair the functions of human trophoblast cells via activation of cell apoptosis and autophagy.

Potato glycoalkaloids and metabolites: roles in the plant and in the diet

Potatoes, members of the Solanaceae plant family, serve as major, inexpensive low-fat food sources providing energy (starch), high-quality protein, fiber, and vitamins. Potatoes also produce biologically active secondary metabolites, which may have both adverse and beneficial effects in the diet. These include glycoalkaloids, calystegine alkaloids, protease inhibitors, lectins, phenolic compounds, and chlorophyll. Because glycoalkaloids are reported to be involved in host-plant resistance and to have a variety of adverse as well as beneficial effects in cells, animals, and humans, a need exists to develop a clearer understanding of their roles both in the plant and in the diet. To contribute to this effort, this integrated review presents data on the (a) history of glycoalkaloids; (b) glycoalkaloid content in different parts of the potato plant, in processed potato products, and in wild, transgenic, and organic potatoes; (c) biosynthesis, inheritance, plant molecular biology, and glycoalkaloid-plant phytopathogen relationships; (d) dietary significance with special focus on the chemistry, analysis, and nutritional quality of low-glycoalkaloid potato protein; (e) pharmacology and toxicology of the potato glycoalkaloids comprising alpha-chaconine and alpha-solanine and their hydrolysis products (metabolites); (f) anticarcinogenic and other beneficial effects; and (g) possible dietary consequences of concurrent consumption of glycoalkaloids and other biologically active compounds present in fresh and processed potatoes. An enhanced understanding of the multiple and overlapping aspects of glycoalkaloids in the plant and in the diet will benefit producers and consumers of potatoes.

Bioavailability and disposition of 3H-solanine in rat and hamster

1. The toxicokinetics of [3H]-alpha-solanine after oral (p.o.) and intravenous (i.v.) administration in rat and hamster were studied, in order to decide which is the most appropriate model in risk assessment studies. The i.v. dose was 54 micrograms/kg; the oral dose was 170 micrograms/kg. 2. After i.v. administration, the toxicokinetics of total radioactivity in blood were comparable in rat and hamster. However, the clearance of total radioactivity from plasma was more effective in rat than in hamster. The half-lives of distribution and of the terminal phase of unchanged alpha-solanine were not different between rat and hamster, whereas the systemic and metabolic clearance were, respectively, about 1.6 and 2.7 times higher in rat than in hamster. The clearance of unchanged alpha-solanine is more effective than of total radioactivity. 3. After p.o. administration in rat and hamster, the mean bioavailability of total radioactivity is about 29 and 57%, respectively. The bioavailability of unchanged alpha-solanine is only 1.6 and 3.2%, respectively, when compared with i.v. administration. 4. T1/2el of alpha-solanine after p.o. administration was in rats a factor of four and in hamsters a factor of two shorter than after i.v. administration. A strong retention of radioactivity was seen in the hamsters after p.o. administration; only 40% of the dose was excreted within 7 days versus 90% in rat. 5. Based on these and toxicological data from literature, it was decided that the hamster is a more appropriate model in (sub)-chronic toxicity studies with alpha-solanine than the rat.