AOB Nitrosospira cluster 3a.2 (D11) dominates N2O emissions in fertilised agricultural soils.

Ammonia-oxidation process directly contribute to soil nitrous oxide (N2O) emissions in agricultural soils. However, taxonomy of the key nitrifiers (within ammonia oxidising bacteria (AOB), archaea (AOA) and complete ammonia oxidisers (comammox Nitrospira)) responsible for substantial N2O emissions in agricultural soils is unknown, as is their regulation by soil biotic and abiotic factors. In this study, cumulative N2O emissions, nitrification rates, abundance and community structure of nitrifiers were investigated in 16 agricultural soils from major crop production regions of China using microcosm experiments with amended nitrogen (N) supplemented or not with a nitrification inhibitor (nitrapyrin). Key nitrifier groups involved in N2O emissions were identified by comparative analyses of the different treatments, combining sequencing and random forest analyses. Soil cumulative N2O emissions significantly increased with soil pH in all agricultural soils. However, they decreased with soil organic carbon (SOC) in alkaline soils. Nitrapyrin significantly inhibited soil cumulative N2O emissions and AOB growth, with a significant inhibition of the AOB Nitrosospira cluster 3a.2 (D11) abundance. One Nitrosospira multiformis-like OTU phylotype (OTU34), which was classified within the AOB Nitrosospira cluster 3a.2 (D11), had the greatest importance on cumulative N2O emissions and its growth significantly depended on soil pH and SOC contents, with higher growth at high pH and low SOC conditions. Collectively, our results demonstrate that alkaline soils with low SOC contents have high N2O emissions, which were mainly driven by AOB Nitrosospira cluster 3a.2 (D11). Nitrapyrin can efficiently reduce nitrification-related N2O emissions by inhibiting the activity of AOB Nitrosospira cluster 3a.2 (D11). This study advances our understanding of key nitrifiers responsible for high N2O emissions in agricultural soils and their controlling factors, and provides vital knowledge for N2O emission mitigation in agricultural ecosystems.

Genipin improves lipid metabolism and sperm parametersin obese mice via regulation of miR-132 expression.

Obesity has now surpassed malnutrition and infectious diseases as the most significant contributor to health problems worldwide. In particular, obesity is associated with several metabolic disorders, including hyperlipidemia, hepatic steatosis, and subfertility. Genipin (GNP), the aglycone of geniposide, is isolated from the extract of the traditional Chinese medicine Gardenia jasminoides Ellis and has been used in traditional oriental medicine against several inflammation-driven diseases. However, the effect and molecular mechanism of GNP on obesity-associated dyslipidemia and sperm dysfunction still need to be explored. In this study, we detect the effects of GNP on hyperlipidemia, hepatic lipid accumulation and sperm function using a high-fat diet (HFD)-induced obese mouse model. We find that obese mice treated with GNP show an improvement in body weight, serum triglyceride levels, serum hormone levels, serum inflammatory cytokines, hepatic steatosis and sperm function. At the molecular level, HFD/GNP diversely regulates the expression of miR-132 in a tissue-specific manner. miR-132 further targets and regulates the expression of SREBP-1c in liver cells, as well as the expressions of SREBP-1c and StAR in Leydig cells in the testis, thus modifying lipogenesis and steroidogenesis, respectively. Collectively, our data demonstrate that GNP shows a broad effect on the improvement of HFD-induced metabolic disorder and sperm dysfunction in male mice by tissue-specific regulation of miR-132. Our findings reveal the function GNP in ameliorating hepatic lipid metabolism and sperm function and suggest that this compound is a versatile drug to treat metabolic disorders.

Genipin improves reproductive health problems caused by circadian disruption in male mice.

BACKGROUND: Circadian rhythm disruption impacts a wide range of physiological processes, including fertility. However, the effect of circadian disruption on male spermatogenesis and fertility, and treatments for these effects have been largely unexplored at the molecular level. METHODS: In this study, we examined the effects of genipin on improving the reproductive health problems caused by circadian disruption. Three groups of animals were fed under different conditions: control group (normal T cycle with saline), group of shortened T cycles (Light/Dark = 4 hours/4 hours) with saline, and a group of shortened T cycles with genipin by oral gavage. The male fertility was evaluated by fertility study and pups parameters analysis after successful sexual behavior and mating with female mice. We sacrificed the treated animals after 5 or 10 weeks and collected the testis, sperm and serum for histological analysis, sperm motility assay, and serum hormone detection, respectively. Furthermore, the effect of genipin was assessed by detection of progesterone secretion and steroidogenic key proteins expression, including StAR and CYP11A1, in mouse Leydig tumor MLTC-1 cells. RESULTS: Male mice exposed to shortened light-dark cycles, much shorter than 24 hours, had reduced fertility with decreased sperm concentrations and sperm motility. Male mice under circadian disruption have reduced testis size and abnormal morphology, leading to lower fertility rates, reduced litter size and pup body weight. Treatment with exogenous genipin, a natural plant-derived compound, alleviated circadian disruption-induced damage to fertility and spermatogenesis and normalized testosterone, dihydrotestosterone (DHT), and androstenedione (ASD) levels in the male mice. The levels of key proteins involved in steroidogenesis, StAR and CYP11A1, were reduced in mouse testes after the circadian disruption, but genipin treatment restored the reduction. The mRNA expression of SRD5A1, which encodes an androgen synthesis enzyme, was also upregulated by genipin treatment. Furthermore, genipin treatment showed a positive effect on steroidogenesis in MLTC-1 cells, resulting in an increase in hormone secretion and the upregulation of StAR and CYP11A1. CONCLUSIONS: Our results showed an association between circadian disruption and reproductive health problems in male mice and indicated that treatments with genipin have positive effects on the reproductive health of male mice with circadian rhythm disorders.

Development of phospholipid vesicle-based permeation assay models capable of evaluating percutaneous penetration enhancing effect.

OBJECTIVES: The phospholipid vesicle-based permeation assay (PVPA) model has recently been introduced as an in vitro model which can mimic stratum corneum (SC) barriers to estimate the skin permeability of drugs. The aim of this study was to evaluate whether the PVPA model was suitable for the evaluation of penetration enhancing effect of skin penetration enhancers (PE). METHODS: The PVPA model was optimized by changing the lipid composition of both small liposomes (SL), and large liposomes (LL). The barrier properties of the PVPA model were monitored by electrical resistance and permeability measurement of the fluorescent marker Rhodamine B (RB). Then the permeation studies of the five active compounds with different physicochemical properties, namely, ferulic acid, paeoniflorin, albiflorin, tetrahydrocolumbamine, and tetrahydropalmatine, were performed directly on PVPA model to evaluate the penetration enhancing effect of menthol. RESULTS AND DISCUSSIONS: The enhancement ratio (ER) ranking of the five active compounds observed using the optimized PVPA model was in accordance with what observed with Franz diffusion cell device using porcine ear skin. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) analysis of PVPA model and porcine ear skin after treatment with menthol has shown similar mechanism of menthol which perturbs the SC lipid arrangement and extracts the SC lipids. CONCLUSIONS: In summary, the optimized PVPA model was used for the first time for the evaluation of the permeation enhancing effect. The optimized PVPA model has shown potential to be applied in a more standardized, cheaper, and ethical way for the screening of PE.

[Testosterone Undecanoate Pills improves insulin resistance in type-2 diabetes men with hypogonadism].

OBJECTIVE: To evaluate the effects of Testosterone Undecanoate Pills (TUP) on insulin resistance (IR) in type-2 diabetes men with hypogonadism. METHODS: We randomly divided 82 type-2 diabetes patients with hypogonadism into a treatment (n = 42) and a control group (n = 40), both maintaining their glucose- and lipid-reducing therapies, while the former treated orally with TUP in addition. After 6 months of medication, we compared the body mass index (BMI), waist circumference (WC), blood glucose level, HbA1c, lipid profile, IR index obtained by homeostatic model assessment (HOMA-IR), insulin sensitivity index (ISI), sex hormone levels, and sexual function scores between the two groups of patients. RESULTS: Compared with the baseline, the patients in the treatment group showed significant decreases after medication in BMI (ï¼»26.71 ± 2.39ï¼½ vs ï¼»25.15 ± 2.28ï¼½ kg/m2, P <0.05), WC (ï¼»89.96 ± 9.13ï¼½ vs ï¼»85.03 ± 9.58ï¼½ cm, P <0.05), HbA1C (ï¼»7.73 ± 1.31ï¼½ vs ï¼»7.01 ± 1.25ï¼½ %, P <0.05), and triglyeride (ï¼»1.97 ± 0.83ï¼½ vs ï¼»1.41 ± 0.69ï¼½ mmol/L, P <0.05), a markedly elevated level of total testosterone (ï¼»7.16 ± 2.21ï¼½ vs ï¼»14.22 ± 2.63ï¼½ nmol/L, P <0.05), and remarkable improvement in HOMA-IR (3.76 ± 1.18 vs 2.55 ± 1.03, P <0.05), ISI (96 ± 51 vs 138 ± 53, P <0.05) and total scores of the Aging Males' Symptoms (P <0.05). But no significant changes were observed in the scores of the International Index of Erectile Function (IIEF) after treatment (13.28 ± 6.38 vs 14.95 ± 6.08, P >0.05). CONCLUSIONS: TUP can significantly improve insulin resistance in type-2 diabetes men with hypogonadism.

Impeding DNA Polymerase ß Activity by Oleic Acid to Inhibit Base Excision Repair and Induce Mitochondrial Dysfunction in Hepatic Cells.

Free fatty acids (FFAs) hepatic accumulation and the resulting oxidative stress contribute to several chronic liver diseases including nonalcoholic steatohepatitis. However, the underlying pathological mechanisms remain unclear. In this study, we propose a novel mechanism whereby the toxicity of FFAs detrimentally affects DNA repair activity. Specifically, we have discovered that oleic acid (OA), a prominent dietary free fatty acid, inhibits the activity of DNA polymerase ß (Pol ß), a crucial enzyme involved in base excision repair (BER), by actively competing with 2'-deoxycytidine-5'-triphosphate. Consequently, OA hinders the efficiency of BER, leading to the accumulation of DNA damage in hepatocytes overloaded with FFAs. Additionally, the excessive presence of both OA and palmitic acid (PA) lead to mitochondrial dysfunction in hepatocytes. These findings suggest that the accumulation of FFAs hampers Pol ß activity and contributes to mitochondrial dysfunction, shedding light on potential pathogenic mechanisms underlying FFAs-related diseases.

[Inhibitory effects of reduced glutathione sodium on renal nuclear factor-kappaB expression in rats with diabetes of different stages].

OBJECTIVE: To investigate the relation between diabetic nephropathy and nuclear factor-kappaB (NF-kappaB) expression, and observe the effect of reduced glutathione sodium (GSH) on NF-kappaB activation and in prevention of diabetic nephropathy. METHODS: Seventy male Sprague-Dawley rats weighing 200-/+25 g were randomized into control group (10 rats) and diabetic group (60 rats, subgrouped into 1 month, 3 months, 6 months and their corresponding intervention subgroups, each consisting of 10 rats). The rats in the 6 diabetic groups were subjected to intraperitoneal injection of streptozotocin, and those in the control group received injection with 0.1 mmol/L citric acid buffer solution of the same volume. The diabetic models were affirmed upon a fasting blood glucose >or=16.5 mmol/L 3 days after the injection. The intervention groups were injected intraperitoneally with GSH (10 mg/100 g) once daily. Fasting blood glucose and body weight were measured every week. The rats were executed at the end of 1, 3, and 6 months respectively and the nucleoproteins were extracted from the renal specimen. NF-kappaB was measured using electrophoretic mobility shift assay (EMSA) after labeling with isotope probe, and the gray scale of the electrophoretic bands was analyzed. RESULTS: EMSA optical density analysis of electrophoretic bands showed that NF-kappaB expression increased in each diabetic groups in comparison with the control group (P<0.05), and NF-kappaB level rose proportionally with the disease course of 1 month, 3 months and 6 months. The activity of NF-kappaB decreased in the intervention groups as compared with the corresponding untreated groups (P<0.05). CONCLUSION: The activation of NF-kappaB plays a role in the onset and development of diabetes. NF-kappaB inhibition and containment of inflammation might be one of the mechanisms of GSH treatment for diabetes.