There is a growing demand for natural sleep aids due to various side effects of long-term administration of pharmacological treatments for insomnia. Honey has been reported to exhibit numerous potential health benefits, and it is hypothesized that honey may favorably affect insomnia treatment. Therefore, this study was performed to investigate the possible hypnotic effect of clover honey (CH) and to determine its in vivo mechanism. The total flavonoid content (TFC) of CH and fractions extracted with ethylacetate (EtOAc) and H2O was measured. The pentobarbital-induced sleep test using GABAA-benzodiazepine (BZD) agonists and antagonists was conducted to evaluate the potential mechanism of action behind the sedative-hypnotic activity of CH in mice. The results showed that administration of 500 and 1,000 mg/kg of CH significantly (p<0.01) reduced the sleep latency to a level similar to that of diazepam (DZP, 2 mg/kg), and 1,000 mg/kg of CH significantly (p<0.01) prolonged the sleep duration, which was comparable to that of DZP (2 mg/kg). Administration of the EtOAc fraction with a higher TFC significantly reduced the sleep latency at 50 to 200 mg/kg and prolonged the sleep duration at 100 to 200 mg/kg, which were comparable to those after administration of DZP (2 mg/kg). However, co-administration of CH and EtOAc with flumazenil, a specific GABAA-BZD receptor antagonist, blocked the hypnotic effect. Our findings suggest that the hypnotic activity of CH may be attributed to allosteric modulation of GABAA-BZD receptors. The TFC of CH is expected to be a key factor that contributes to its hypnotic effect.

In this study, oocyte steroidogenesis are investigated in relation to oocyte development in the starry flounder, Platichthys stellatus, a marine multiple spawner. Vitellogenic (0.52 and 0.55 mm oocyte diameter) and mature oocytes (0.63, 0.66 and 0.71 mm oocyte diameter) were incubated in vitro in the presence of [3H]17α-hydroxyprogesterone ([3H]17α- OHP) as a precursor. Steroid metabolites were extracted from the incubated media and oocytes, the extracts were separated and identified by thin-layer chromatography (TLC), high performance liquid chromatography (HPLC) and gas chromatographymass spectrometry (GC-MS). The major metabolites produced from [3H]17α-OHP were androgens [androstenedione (A4) and testosterone (T)] and estrogens [17β-estradiol (E2) and estrone (E1)] and progestins [17α,20α-dihydroxy-4-pregnen- 3-one (17α20αP) and 17α,20β-dihydroxy-4-pregnen-3-one (17α20βP)] in vitellogenic and mature oocytes. The results from this study suggest the potential roles of E1 in the oocytes with diameter 0.52-0.71 mm, 17α20αP and 17α20βP at the oocytes of 0.63, 0.66 and 0.71 mm.

Human serum (HS) has been reported to induce aggregation of human eyelid adipose-derived stem cells (HEACs) during high-density culture in vitro. The present study focused on the role of cell adhesion molecules and gelatinases during HS-induced aggregation of HEACs. HS-induced aggregation occurred between 9-15 days of culture. Cells aggregated by HS medium (HS-agg) showed stronger expression of α2, α2B, αX, and CEACAM1 genes compared to non-aggregated cells in HS medium (HS-ex) or in control FBS-cultured cells. HS-agg were distinctly labeled with antibodies against α2, α2B, and αX proteins. Western blot results demonstrated that the two integrin proteins were greatly expressed in HS-agg compared to HS-ex and control FBS-cultured cells. Treatment of HEACs with anti-integrin α2 antibody during culture in HS medium delayed aggregation formation. HS-agg exhibited strong expression of MMP1 and MMP9 compared to HS-ex or FBS-cultured cells. Conditioned media from HS-culture showed remarkable increase of MMP9 gelatinolytic activity in comparison to those from FBS-culture. However, there was no change of TIMP mRNA expression in relation to the HS-induced aggregation. Based on these results, it is suggested that integrin α2, α2B, and αX, and MMP9 might play an important role in the HS-induced aggregation of HEACs.