The protective effect and underlying mechanism of Hainan papaya water extract against neuronal apoptosis induced by Aß40.

OBJECTIVE: To investigate whether Hainan papayas has protective effects in an Aß40-induced primary neuron injury model and elucidate the underlying molecular mechanism. METHODS: Cultured primary neurons from the dorsal root ganglia (DRG) of Sprague-Dawley (SD) rats were treated with 20 µM Aß40 peptide, 100 µg/L Hainan papaya water extract, peptide plus extract, or culture medium for 24 h. Cell viability was measured by MTT assay, and neuronal apoptosis was evaluated by DAPI staining. ERK signaling pathway-associated molecule activation and changes in Bax expression were analyzed by Western blotting and immunofluorescence. RESULTS: A cell viability rate of (44.11 ± 6.59)% in the Aß40 group was rescued to (79.13 ± 6.64)% by adding different concentrations of the extract. DAPI showed pyknotic nuclei in 39.5% of Aß40-treated cells; the fraction dropped to 17.4% in the 100 µg/L extract group. ERK phosphorylation was observed in the Aß40 group but was ameliorated by pretreatment with 100 µg/L extract. Hainan papaya water extract also prevented Aß40-induced phosphorylation of MEK, RSK1 and CREB associated with ERK signaling and downregulated Bax expression in the neurons. CONCLUSION: The results suggest that Hainan papaya water extract has protective effects on neurons; the mechanism may be related to suppression of ERK signaling activation.

Correlation between the Xba I polymorphism of apoB gene and serum lipid profiles in Li ethnic group.

OBJECTIVE: To study correlation between the Xba I polymorphism of apoB gene and plasma lipid profiles in Li ethnic group. METHODS: Total 151 cases of healthy Li people were recruited randomly by cluster sampling and 200 Han people were recruited as control; blood was drawn to analyze Xba I polymorphism distribution of apoB gene and serum lipid levels. RESULTS: There were lower serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) levels in serum of Li people; while, high density lipoprotein cholesterol (HDL-C), X-/X+ genotype and X+ allele frequencies exhibited higher levels than Han people. Interestingly, HDL-C level was reduced, while LDL-C level was enhanced in subjects carrying heterozygous (X-/X+) genotype compared to homozygous (X-/X-) genotype. Additionally, there were no difference in serum level of triglyceride, TC, apoprotein A (apo A) and apoprotein B (apo B) between Li and Han people, the same results were showed between X-/X+ and X-/X- genotype carriers. CONCLUSIONS: Xba I polymorphism of apoB gene is correlated to the profiles of serum lipid level, X-/X+ genotype carriers are phenotyped with higher LDL-C level and lower level of HDL-C in Li ethnic group.

[Protecting actions of Peristrophe roxburghiane on liver functions and structure in fatty liver rats caused by insulin resistance].

OBJECTIVE: To observe the protecting actions of Peristrophe roxburghiane on liver functions and structure in fatty liver rats caused by insulin resistance. METHOD: High-fat-sugar diet was fed in rats to produce insulin resistance and fatty liver model, and then P. roxburghiane was administered for 8 weeks, and the rats were killed and the blood was sampled to measure the levels of FFA, TC, TG, HDL-C and LDL-C, and the activities of AST, ALT. The fasting serum glucose (FBG) and insulin were measured, and insulin-sensitivity index was calculated. The liver was weighed and collected to calculate liver index and measured the activities of GSH-PX, SOD, CAT and the amount of MDA. RESULT: High and low dosage of P. roxburghiane can decrease the levels of FFA, TG and increase the level of HDL-C, reduce the activities of ALT, AST and liver index, and reduce the damaged degree of the liver tissue significantly. High and low dosage of P. roxburghiane can significantly enhance the activities of SOD, CAT, and GSH-PX, reduce the amount of MDA. CONCLUSION: P. roxburghiane possesses regulating action on the serum lipid, blood glucose and insulin, and improving liver functions of fatty liver rats induced by high-fat-sugar diet, and the acting mechanism may be concerned with enhanced antioxidative ability.