Quercetin potentiates docosahexaenoic acid to suppress lipopolysaccharide-induced oxidative/inflammatory responses, alter lipid peroxidation products, and enhance the adaptive stress pathways in BV-2 microglial cells

High levels of docosahexaenoic acid (DHA) in the phospholipids of mammalian brain have generated increasing interest in the search for its role in regulating brain functions. Recent studies have provided evidence for enhanced protective effects when DHA is administered in combination with phytochemicals, such as quercetin. DHA and quercetin can individually suppress lipopolysaccharide (LPS)-induced oxidative/inflammatory responses and enhance the antioxidative stress pathway involving nuclear factor erythroid-2 related factor 2 (Nrf2). However, studies with BV-2 microglial cells indicated rather high concentrations of DHA (IC 50 in the range of 60-80 µM) were needed to produce protective effects. To determine whether quercetin combined with DHA can lower the levels of DHA needed to produce protective effects in these cells is the goal for this study. Results showed that low concentrations of quercetin (2.5 µM), in combination with DHA (10 µM), could more effectively enhance the expression of Nrf2 and heme oxygenase 1 (HO-1), and suppress LPS-induced nitric oxide, tumor necrosis factor-[alpha], phospho-cytosolic phospholipase A 2 , reactive oxygen species, and 4-hydroxynonenal, as compared to the same levels of DHA or quercetin alone. These results provide evidence for the beneficial effects of quercetin in combination with DHA, and further suggest their potential as nutraceuticals for improving health

Beta 3 adrenergic receptor activation rescues metabolic dysfunction in female estrogen receptor alpha-null mice

Metabolic disease risk escalates following menopause. The mechanism is not fully known, but likely involves reduced signaling through estrogen receptor alpha (ER[alpha]), which is highly expressed in brown and white adipose tissue (BAT and WAT). Objective: Test the hypothesis that uncoupling protein (UCP1) activation mitigates metabolic dysfunction caused by loss of signaling through ER[alpha]. Methods: At 8 weeks of age, female ER[alpha] knock out (KO) and wild-type mice were housed at 28∘C and fed a Western-style high-fat, high sucrose diet (HFD) or a normal low-fat chow diet (NC) for 10 weeks. During the final 2 weeks, they received daily injections of CL 316,256 (CL), a selective [beta]3 adrenergic agonist, or vehicle control (CTRL), creating eight groups: WT-CTRL, WT-CL, KO-CTRL, and KO-CL on HFD or NC; n = 4–10/group. Results: ER[alpha]KO demonstrated exacerbated HFD-induced adiposity gain (P < 0.001) and insulin resistance (P = 0.006). CL treatment improved insulin sensitivity (P < 0.05) and normalized ER[alpha]KO-induced adiposity increase (P < 0.05). In both genotypes, CL increased resting energy expenditure (P < 0.05) and induced WAT beiging indicated by increased UCP1 protein in both perigonadal (PGAT) and subcutaneous (SQAT) depots. These effects were attenuated under HFD conditions (P < 0.05). In KO, CL reduced HFD energy consumption compared to CTRL (P < 0.05). Remarkably, CL increased WAT ER[beta] protein levels of both WT and KO (P < 0.001), revealing CL-mediated changes in estrogen signaling may have protective metabolic effects. Conclusion: CL completely restored metabolic dysfunction in ER[alpha]KO mice. Thus, UCP1 may be a therapeutic target for treating metabolic dysfunction following loss of estrogen receptor signaling. Copyrigh

Factor IX gene haplotypes in Brazilian Blacks and characterization of unusual Ddel alleles

Analysis of factor IX gene polymorphisms is considered the best approach for prenatal diagnosis and carrier detection of haemophilia B when the identification of the gene mutation is not possible. Studies involving factor IX gene polymorphisms in Black populations are scarce and essentially restricted to the North-American Black population whose composition is substantially different from that of the Brazilian and presumably other Black populations of South America. In this paper we report the analysis of eight factor IX gene polymorphisms in Brazilian Blacks: 5’ BamHI, DdeI, intron 2 BamHI, XmnI, TaqI, MspI, MnII and HhaI. Characterization of the VNTR-like Ddel polymorphism revealed six different alleles: B, AB, A2B, A2B2, A3B and A5, the last being described here for the first time. The 5’ BamHI, DdeI, MspI and Hhal polymorphisms showed the highest heterozygosities (0.40-0.50) and are in linkage equilibrium with one another. 19 complete haplotypes could be identified in this population. Based on the results we propose a systematic strategy for carrier detection and prenatal diagnosis of haemophilia B in this population. The combined analysis of four polymorphisms (5’ BamHI, HhaI, MspI and DdeI) provided an informative genetic marker in 85% of the females. The use of all eight polymorphisms allows information in 95% of females. Additionally, differences in gene frequencies and haplotype distribution suggest dissimilarities in factor IX gene polymorphisms between the Brazilian and the North-American Black populations

Androgen dependent stimulation of aromatase activity in genital skin fibroblasts from normals and patients with androgen insensitivity

objective To measure the effect of androgens or aromatase activity as an index of androgen responsiveness in patients with androgen insensitivity design Genital skin fibroblasts were established in culture using primary skin explants obtained from normal males at the time of circumcision and from androgen insensitive patients who had surgery either for gonadectomy (complete androgen insensitivity syndrome) or for reconstruction of the external genitalia (partial androgen insensitivity syndrome) patients Foreskin samples were obtained at the time of circumcision in 27 normal males. Scrotal or labla majora skin was obtained at the time of surgery from 14 patients with the complete and 22 with the partial forms of the androgen insensitivity syndrome measurements Basal and stimulated levels of aromatase activity were measured in genital skin fibroblasts following preincubation with natural and synthetic, non-metabolizable androgens results Following a 48-hour preincubation with testosterone or dihydrotestosterone, there was a five to six-fold stimulation of aromatase activity in normal fibroblasts. Mibolerone, a synthetic androgen, produced similar results. The stimulatory effect was blocked by anti-androgens. Seven patients with partial androgen insensitivity, of whom four were either receptor deficient or showed a qualitative defect in androgen binding, had reduced mibolerone induced stimulation of aromatase activity. All ten patients with receptor negative complete androgen insensitivity had an absent response. There was no aromatase induction in a further three patients with complete androgen insensitivity who were receptor positive. Two siblings in the latter group had an exon deletion encoding for part of the DNA binding domain of the androgen receptor conclusions Androgens stimulate aromatase activity in genital skin fibroblasts from normals. The response is mediated via the androgen receptor and can be decreased or absent in patients with the androgen insensitivity syndrome. This may be a useful in-vitro marker of androgen responsiveness in such patient