The hypothalamic steroidogenic pathway mediates susceptibility to inflammation-evoked depression in female mice.

BACKGROUND: Depression is two-to-three times more frequent among women. The hypothalamus, a sexually dimorphic area, has been implicated in the pathophysiology of depression. Neuroinflammation-induced hypothalamic dysfunction underlies behaviors associated with depression. The lipopolysaccharide (LPS)-induced mouse model of depression has been well-validated in numerous laboratories, including our own, and is widely used to investigate the relationship between neuroinflammation and depression. However, the sex-specific differences in metabolic alterations underlying depression-associated hypothalamic neuroinflammation remain unknown. METHODS: Here, we employed the LPS-induced mouse model of depression to investigate hypothalamic metabolic changes in both male and female mice using a metabolomics approach. Through bioinformatics analysis, we confirmed the molecular pathways and biological processes associated with the identified metabolites. Furthermore, we employed quantitative real-time PCR, enzyme-linked immunosorbent assay, western blotting, and pharmacological interventions to further elucidate the underlying mechanisms. RESULTS: A total of 124 and 61 differential metabolites (DMs) were detected in male and female mice with depressive-like behavior, respectively, compared to their respective sex-matched control groups. Moreover, a comparison between female and male model mice identified 37 DMs. We capitalized on biochemical clustering and functional enrichment analyses to define the major metabolic changes in these DMs. More than 55% of the DMs clustered into lipids and lipid-like molecules, and an imbalance in lipids metabolism was presented in the hypothalamus. Furthermore, steroidogenic pathway was confirmed as a potential sex-specific pathway in the hypothalamus of female mice with depression. Pregnenolone, an upstream component of the steroid hormone biosynthesis pathway, was downregulated in female mice with depressive-like phenotypes but not in males and had considerable relevance to depressive-like behaviors in females. Moreover, exogenous pregnenolone infusion reversed depressive-like behaviors in female mice with depression. The 5α-reductase type I (SRD5A1), a steroidogenic hub enzyme involved in pregnenolone metabolism, was increased in the hypothalamus of female mice with depression. Its inhibition increased hypothalamic pregnenolone levels and ameliorated depressive-like behaviors in female mice with depression. CONCLUSIONS: Our study findings demonstrate a marked sexual dimorphism at the metabolic level in depression, particularly in hypothalamic steroidogenic metabolism, identifying a potential sex-specific pathway in female mice with depressive-like behaviors.

Discovery of a potent anti-yeast triterpenoid saponin, clematoside-S from Urena lobata L.

Urena lobata has been used as a traditional medicinal plant in India and China. In this study, we investigated the antimicrobial activity and isolated the active compound from the leaves of U. lobata. The 80% ethanol extract from U. lobata leaves showed an effective anti-yeast activity against Saccharomyces cerevisiae (S. cerevisiae) strains. Using a combination of chromatographic methods, (-)-trachelogenin (1) and clematoside-S (2) were isolated from this plant for the first time, and their chemical structure was identified by mass spectrometry (MS) and extensive nuclear magnetic resonance (NMR) data analysis. In addition, 1 was found to be inactive against all of the test microorganisms in the antimicrobial assay, whereas 2 exhibits a specific anti-yeast activity against S. cerevisiae strains with diameter of inhibition zones in the range from 11 to 20 mm. Furthermore, the MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration) values of 2 against S. cerevisiae strains were detected to be in the ranges of 0.61 to 9.8 µg/mL and 2.42 to 9.8 µg/mL, respectively. This is the first report of 2 with a specific anti-yeast activity. The above result suggests the potential application of U. lobata to be used as a natural anti-yeast agent in food preservation.

Intestinal alpha-glucosidase inhibitory activity and toxicological evaluation of Nymphaea stellata flowers extract.

AIM OF THE STUDY: Nymphaea stellata willd. flowers (NSF) are used as a traditional medicine in India and Nepal to treat diabetic disease. Different works have demonstrated that NSF extract showed antihyperglycemic effect on alloxan-induced diabetic rats. In the present work we evaluated in vitro intestinal alpha-glucosidase inhibition as the possible mode of action of NSF extract on suppressing postprandial hyperglycemia for curing diabetic mellitus. In addition, NSF extract was studied to assess its possible acute oral toxicity and genotoxicity. MATERIALS AND METHODS: Rat intestinal crude enzyme preparation and Caco-2 monolayer were used to evaluate alpha-glucosidase inhibitory activity of NSF extract. The main alpha-glucosidase inhibitors were detected by HPLC. For acute toxicity test, NSF extract was administered at doses of 2000, 5000 and 10,000 mg/kg body to three groups of 10 ICR mice each, and then clinical symptoms including mortality, clinical sign and gross findings were observed once a day for 14 days. In Ames test, histidine-dependent auxotrophic mutants of Salmonella typhimurium (strains TA97, TA98, TA100, TA102 and TA1535) were used and incubated in the presence and absence of S9 metabolic activation using NSF extract with concentrations of 150-5000 microg/plate. The chromosome aberration test was conducted with Chinese hamster lung (CHL) cells treated with NSF extract at doses of 150-5000 microg/ml in the presence and absence of S9 metabolic activation. In the in vivo mouse micronucleus assay, 9-week-old male and female ICR mice (n=90, 25-30 g) were administered daily by oral gavage at doses of 2.5, 5.0 and 10.0 g/kg body for 1 or 2 days. Bone marrow smears were prepared from each treatment group 24h after last administration and then polychromatic erythrocytes (PCEs) and normochromatic erythrocytes (NCEs) were identified. RESULTS: NSF extract showed potent rat intestinal alpha-glucosidase inhibitory activity for maltose hydrolysis with ED(50) value of 0.1 mg/ml. In Caco-2 monolayer, alpha-glucosidase activity for the maltose hydrolysis was down-regulated by NSF extract at a concentration of 0.05 mg/well level, showing 74% inhibition compared to the saline treated control. NSF was rich in phenol contents and the main alpha-glucosidase inhibitor, 1,2,3,4,6-penta-O-galloyl-beta-D-glucose, was identified together with two phenolic compounds of gallic acid and corilagin. In acute toxicity test, NSF extract did not produce any toxic signs or deaths and the LD(50) value of this extract could be greater than 10,000 mg/kg body weight. These results of genotoxicity assessment showed that NSF extract did not cause genotoxic effects in Ames test, in the in vitro chromosomal aberration assay and in the in vivo micronucleus assay. CONCLUSION: The current study shows that the extract from Nymphaea stellata flowers exhibits significant intestinal alpha-glucosidase inhibitory activity, without showing any acute toxicity or genotoxicity, which may be useful in suppressing postprandial hyperglycemia in diabetics. The results presented here suggest that the use of NSF in folk medicine as a natural antidiabetic treatment could be safe as well as beneficial.

[Effects of Sijunzi Decoction on urine's xylose excretion rate and ATP in mucosa of spleen deficiency rats].

OBJECTIVE: To observe the effects of Sijunzi Decoction on D-xylose excretion rate and ATP content in the mucosa membranes of small intestines of rats with spleen deficiency. METHODS: Spleen deficiency model rats were made by reserpine injection. D-xylose excretion rate was measured with p-bromoaniline method, and the ATP content of small intestines mucosa was detected with bioluminescence method. The correlation between D-xylose excretion rate and ATP content of mucosa was also analyzed. RESULTS: Rats' body weight and D-xylose excretion rate decreased after reserpine injection (P < 0.01, vs control group), but increased after treated with Sijunzi Decoction (P < 0.05, vs model group). The ATP content of mucosa showed no significant difference between model group and control group. There was obviously positive correlation between the change of urine's D-xylose excretion rate and mucosa ATP content. CONCLUSION: Sijunzi Decoction has the activity of improving xylose absorption in spleen deficiency rats, but no obvious effect on their mucosa ATP content. The reducing of urine's D-xylose excretion rate in spleen deficiency rats is accompanied with the decrease of mucosa ATP content.

[Study on relationship among thyroid hormone relativity and Syndrome Differentiation-types of TCM in patients with congestive heart failure].

OBJECTIVE: To study the relationship between the TCM Syndrome Differentiation-types of congestive heart failure (CHF) and thyroid hormones, including triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH), and atrial natriuretic peptide (ANP), as well as cardiac function parameters, including left ventricular ejection fraction (LVEF), mean velocity of circumferentid fiber shortening (mVcf) and A peak/E peak (A/E). METHODS: One hundred patients with CHF were divided into 4 Syndrome Differentiation-type groups, their cardiac function parameters, ANP and thyroid hormones were determined and compared with those in the 23 subjects in the control group. RESULTS: In CHF patients with edema and blood stasis Syndrome type, the level of plasma ANP was significantly higher than that in the control group (P < 0.05); level of T3 was significantly lower than that in the control group and in CHF patients of other three (Xin-qi deficiency, Yin-deficiency and blood stasis) Syndrome groups (P < 0.01, P < 0.01, P < 0.05 and P < 0.01); levels of LVEF and mVcf were significantly lower than those in the other three Syndrome groups (all P < 0.01). Level of T4 in other three Syndrome groups significantly increased than that in the edema and blood stasis Syndrome type. A/E value showed a higher level in patients of all TCM type than that in the control (P < 0.01). Correlation analysis showed that T3 was positively correlated with LVEF and T4 (r = 0.200, P < 0.05, and r = 0.293, P < 0.01), and negatively correlated with ANP (r = -0.263, P < 0.01); T4 was negatively correlated with A/E (r = -0.226, P < 0.05). CONCLUSION: The lowering of T3 and T4 and increasing of ANP may be one of the important reasons for lowering of LVEF in CHF patients with edema and blood stasis Syndrome-type. The decrease of T4 may be one of the important reasons for elevation of A/E and aggravation of left ventricular diastolic dysfunction in CHF patients of all the 4 TCM Syndrome-types.