Genome-wide analysis of gustatory receptor genes and identification of the fructose gustatory receptor in Arma chinensis.

Gustatory receptors (GRs) allow insects to sense tastes in their external environment. Gustatory perception is crucial for distinguishing between beneficial and harmful or toxic compounds, affecting survival. This study is the first to identify and classify the GR genes and investigate their expression in the predatory Arma chinensis. Thirteen GR genes (ArmaGr1-ArmaGr13) were identified and classified into four families via phylogenetic analysis. In the predacious developmental stages, ArmaGr7 expression gradually increased from the 2nd to 5th instar stages and then to adults. However, ArmaGr7 was also highly expressed in the non-predation 1st instar nymph and egg stages. ArmaGr7 expression was localized in the antennae, scalpella, forelegs, wings, head, and midgut of male and female adults, with wings displaying the highest expression. Furthermore, ArmaGr7 expression was positively correlated with fructose solution intake; molecular docking results showed that fructose could effectively dock withArmaGr7. A protein structure comparison revealed that the ArmaGr7 structure was different from that of other GR43a-like proteins, which may be related to the gene splicing of the A. chinensis GR gene. These results elucidate the crucial role of ArmaGr7 in fructose recognition by A. chinensis and provide a foundation for further studies on gustatory perception.

Histone demethylase KDM1A promotes hepatic steatosis and inflammation by increasing chromatin accessibility in NAFLD.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease without specific Food and Drug Administration-approved drugs. Recent advances suggest that chromatin remodeling and epigenetic alteration contribute to the development of NAFLD. The functions of the corresponding molecular modulator in NAFLD, however, are still elusive. KDM1A, commonly known as lysine-specific histone demethylase 1, has been reported to increase glucose uptake in hepatocellular carcinoma. In addition, a recent study suggests that inhibition of KDM1A reduces lipid accumulation in primary brown adipocytes. We here investigated the role of KDM1A, one of the most important histone demethylases, in NAFLD. In this study, we observed a significant upregulation of KDM1A in NAFLD mice, monkeys, and humans compared to the control group. Based on these results, we further found that the KDM1A can exacerbate lipid accumulation and inflammation in hepatocytes and mice. Mechanistically, KDM1A exerted its effects by elevating chromatin accessibility, subsequently promoting the development of NAFLD. Furthermore, the mutation of KDM1A blunted its capability to promote the development of NAFLD. In summary, our study discovered that KDM1A exacerbates hepatic steatosis and inflammation in NAFLD via increasing chromatin accessibility, further indicating the importance of harnessing chromatin remodeling and epigenetic alteration in combating NAFLD. KDM1A might be considered as a potential therapeutic target in this regard.

Protective effect of a phenolic extract containing indoline amides from Portulaca oleracea against cognitive impairment in senescent mice induced by large dose of D-galactose /NaNO2.

ETHNOPHARMACOLOGICAL RELEVANCE: Portulaca oleracea L. is a potherb and also a widely used traditional Chinese medicine. In accordance with its nickname "longevity vegetable", pharmacological study demonstrated that this plant possessed antioxidant, anti-aging, and cognition-improvement function. Active principles pertaining to these functions of P. oleracea need to be elucidated. AIM OF THE STUDY: The present study evaluated the effect of a phenolic extract (PAAs) from P. oleracea which contained specific antioxidant indoline amides on cognitive impairment in senescent mice. MATERIALS AND METHODS: PAAs was prepared through AB-8 macroporous resin column chromatography. Total phenol content was determined using colorimetric method, and contents of indoline amides were determined using HPLC-UV method. Senescent Kunming mice with cognitive dysfunction were established by intraperitoneal injection of D-galactose (D-gal, 1250mg/kg/day) and NaNO2 (90mg/kg/day) for 8 weeks, L-PAAs (360mg/kg/day), H-PAAs (720mg/kg/day), and nootropic drug piracetam (PA, 400mg/kg/day) as the positive control were orally administered. Spatial learning and memory abilities were evaluated by Morris water maze experiment. Activities of AChE, SOD, CAT, and levels of GSH and MDA in the brain or plasma were measured. Hippocampal morphology was observed by HE staining. RESULTS: Chronic treatment of large dose of D-gal/NaNO2 significantly reduced lifespan, elevated AChE activity, decreased CAT activity, compensatorily up-regulated SOD activity and GSH level, increased MDA level, induced neuronal damage in hippocampal CA1, CA3 and CA4 regions, and impaired cognitive function. Similar to PA, PAAs prolonged the lifespan and improved spatial memory ability. Moreover, PAAs improved learning ability. H-PAAs significantly reversed compensatory increase in SOD activity to the normal level, elevated serum CAT activity, and reduced MDA levels in brain and plasma, more potent than L-PAAs. Besides these, PAAs evidently inhibited hippocampal neuronal damage. However, it had no effect on brain AChE activity. CONCLUSION: PAAs as the bioactive principles of P. oleracea attenuated oxidative stress, improved survival rate, and enhanced cognitive function in D-gal/NaNO2-induced senile mice, similar to piracetam. This phenolic extract provides a promising candidate for prevention of aging and aging-related cognitive dysfunction in clinic.

[Bioactivity diversity and functional mechanism of tetrahydroisoquinoline alkaloids].

Tetrahydroisoquinoline alkaloids distributed widely in the nature and some have a broad application in clinic. More attention has been paid in recent years on this type of alkaloid, owing to the diverse range of biological activities exhibited by these alkaloids and the discovery of new functional mechanisms and molecular targets underlying these activities. This article summarized the recent advances in the biological activities and functional mechanism of tetrahydroisoquinoline, which included the activities such as antitumor, antibiotic, antivirus, anti-inflammatory, anticoagulation, bronchodilation, and the action on central nervous system, with the purpose of providing some ideas in the study of biological activity of this type of alkaloid and in the search for lead-compound and rational drug design.

[Studies on the chemical constituents of Portulaca oleracea].

OBJECTIVE: To study the chemical constituents of Portulaca oleracea. METHODS: The constituents were isolated by column chromatography and identified on the basis of physicochemical and spectral data. RESULTS: Five compounds were isolated from 70% ethanol extract of this plant and their structures were elucidated as cyclo (Phe-Ile) (1), cycle (Tyr-Ala) (2), adenine (3), friedelin (4) and isoselachoceric acid (5). CONCLUSION: Compounds 1-5 are isolated from Portulaca oleracea for the first time.