Sustainable valorizing high-protein feather waste utilization through solid-state fermentation by keratinase-enhanced Streptomyces sp. SCUT-3 using a novel promoter.

Feather waste, a rich source of proteins, has traditionally been processed through high-temperature puffing and acid-base hydrolysis, contributing to generation of greenhouse gases and H2S. To address this issue, we employed circular economy techniques to recover the nutritional value of feather waste. Streptomyces sp. SCUT-3, an efficient proteolytic and chitinolytic bacterium, was isolated for feather degradation previously. This study aimed to valorize feather waste for feed purposes by enhancing its feather transformation ability through promoter optimization. Seven promoters were identified through omics analysis and compared to a common Streptomyces promoter ermE*p. The strongest promoter, p24880, effectively enhanced the expression of three candidate keratinases (Sep39, Sep40, and Sep53). The expression efficiency of double-, triple-p24880 and sandwich p24880-sep39-p24880 promoters were further verified. The co-overexpression strain SCUT-3-p24880-sep39-p24880-sep40 exhibited a 16.21-fold increase in keratinase activity compared to the wild-type. Using this strain, a solid-state fermentation process was established that increased the feather/water ratio (w/w) to 1:1.5, shortened the fermentation time to 2.5 days, and increased soluble peptide and free amino acid yields to 0.41 g/g and 0.14 g/g, respectively. The resulting has high protein content (90.49 %), with high in vitro digestibility (94.20 %). This method has the potential to revolutionize the feather waste processing industry.

Luteolin Enhances Choroid Plexus 5-MTHF Brain Transport to Promote Hippocampal Neurogenesis in LOD Rats.

Folates, provided by food, are commonly used antidepressant synergists in late-onset depression (LOD). However, increased intake of folic acid in the elderly population might lead to the accumulation of unmetabolized folic acid in the systemic circulation, leading to enhanced deterioration of the central nervous system function. In addition, folates cannot access the brain directly because of the blood-brain barrier. Choroid plexus (CP) 5-methyltetrahydrofolate (5-MTHF) brain transport plays a critical role in regulating the cerebrospinal fluid (CSF) 5-MTHF content. Luteolin is a natural flavonoid that has antidepressant effects and is involved in the anti-folate resistance pathway. It remains unclear whether the antidepressant effects of luteolin are associated with the CP 5-MTHF brain transport. In this study, 20-21-month-old Wistar rats were exposed to the chronic unpredictable mild stress (CUMS) protocol for 6 consecutive weeks to explore the long-term effects of luteolin on behavior, 5-MTHF levels, hippocampal neurogenesis, and folate brain transport of the CP. In vitro primary hippocampal neural stem cells (NSCs) cultured in media containing 10% CSF from each group of rats and choroid plexus epithelial cells (CPECs) cultured in media containing 20 µM luteolin were treated with 100 µM corticosterone and 40 mg/ml D-galactose. We found that aged rats exposed to CUMS showed a significantly reduced sucrose preference, decreased locomotion activity in the open field test and accuracy of the Morris water maze test, increased immobility time in the forced swimming test, accelerated dysfunctional neurogenesis and neuronal loss in the dentate gyrus of LOD rats, as well as decreased CSF and hippocampus 5-MTHF levels, and zona occludens protein 1 (ZO-1), proton-coupled folate transporter (PCFT), and reduced folate carrier (RFC) protein levels. In vitro assays showed media containing 10% aged CSF or LOD+ Luteolin-CSF significantly increased the viability of CORT + D-gal-injured NSCs and alleviated dysfunctional neurogenesis and neuronal loss compared with the CORT + D-gal medium. However, media containing 10% LOD-CSF had no such effect. In the meantime, induction of CORT + D-gal significantly decreased the ZO-1, PCFT, RFC, and folate receptor alpha (FR-α) protein levels and transepithelial electrical resistance in rat CPECs. As expected, luteolin treatment was effective in improving these abnormal changes. These findings suggested that luteolin could ameliorate CUMS-induced LOD-like behaviors by enhancing the folate brain transport.

[Preliminary study on cerebrospinal fluid proteomics of Erxian Decoction against neurogenesis impairment in late-onset depression].

This study aims to elucidate the underlying mechanism of Erxian Decoction(EXD) against neurogenesis impairment in late-onset depression(LOD) rats based on cerebrospinal fluid(CSF) proteomics. A total of 66 20-21-month-old male Wistar rats were randomized into naturally aged(AGED) group, LOD group, and EXD group. All rats received chronic unpredictable mild stress(CUMS) for 6 weeks for LOD modeling except for the AGED group. During the modeling, EXD group was given EXD(ig, twice a day at 4 g·kg~(-1)) and other groups received equivalent amount of normal saline(ig). After modeling, a series of behavioral tests, such as sucrose preference test(SPT), open-field test(OFT), forced swimming test(FST), and Morris water maze test(MWMT) were performed. Immunofluorescence method was used to detect the number of Ki-67/Nesti-positive cells and BrdU/DCX-positive cells in the hippocampal DG area of each group. High-concentration corticosterone(CORT) was combined with D-galactose(D-gal) to simulate the changes of LOD-related stress and aging and the proliferation and differentiation of primary neural stem cells of hippocampus in each group were observed. Data independent acquisition(DIA)-mass spectrometry(MS) was used to analyze the differential proteins in CSF among groups and bioinformatics analysis was performed to explore the biological functions of the proteins. Behavioral tests showed that sucrose consumption in SPT, total traveling distance in OFT, and times of crossing the platform in MWMT were all reduced(P<0.01) and the immobility time in FST was prolonged(P<0.01) in the LOD group compared with those in the AGED group, suggesting that LOD rats had developed depression symptoms such as anhedonia, decreased locomotor activity ability, and cognitive dysfunction. Behavioral abnormalities were alleviated(P<0.01, P<0.05) in the EXD group as compared with those in the LOD group. Immunofluorescence results demonstrated that Ki-67/Nesti-positive cells and BrdU/DCX-positive cells in the hippocampal DG area were fewer(P<0.05) in LOD group than in the AGED group, and the positive cells in the EXD group were more(P<0.05) than those in the LOD group. In vitro experiment showed that the proliferation and differentiation of primary hippocampal neural stem cells under the CORT+D-gal treatment were reduced(P<0.01). The proliferation rate of neural stem cells decreased(P<0.05) in CORT+D-gal+LOD-CSF group but increased(P<0.01) in CORT+D-gal+EXD-CSF group compared with that in the CORT+D-gal group. A total of 2 620 proteins were identified from rat CSF, with 135 differential proteins between the LOD group and AGED group and 176 between EXD group and LOD group. GDF11, NrCAM, NTRK2, and GhR were related to neurogenesis and 39 differential proteins were regulated by both LOD and EXD. EXD demonstrated obvious anti-LOD effect, as it improved the locomotor activity ability and cognitive function of LOD rats and protected the proliferation and differentiation of hippocampal neural stem cells. EXD exerts anti-LOD effect by regulating the proteins related to neurogenesis in CSF, such as GDF11, NrCAM, NTRK2, and GhR and maintaining hippocampal neurogenesis.

Remodeling of rat pulmonary artery induced by chronic smoking exposure.

OBJECTIVE: To evaluate the dominant role in rat pulmonary artery (PA) remodeling induced by chronic smoking exposure (CSE). METHODS: Thirty-five male Sprague-Dawley (SD) rats were exposed to 36 cigarettes per day, 6 days per week, for 1, 3, or 5 months. Another 35 SD rats were sham-exposed during the same period. Hemodynamic measurement, evaluation of the right ventricular hypertrophy index (RVHI) plus right ventricle-to-weight ratio, and hematoxylin eosin staining was performed. Wall thickness, artery radius, luminal area, and total area were measured morphometrically. Western blotting assessed expression of PPAR-γ BMP4, BMPR2, and TRPC1/4/6 in the artery and lung. Store-operated calcium entry (SOCE) and [Ca(2+)]i were measured using Fura-2 as dye. RESULTS: Mean right ventricular pressure increased after 3 months of smoking exposure and continued to increase through 5 months. Right ventricular systolic pressure (RVSP) increased after 3 months of exposure and then stabilized. RVHI increased after 5 months; right ventricle-to-weight ratio was elevated after 3 months and further increased after 5 months. Wall thickness-to-radius ratio does-dependently increased after 3 months through 5 months, in parallel with the decreased luminal area/total area ratio after 5 months. Other changes included the development of inflammatory responses, enlargement of the alveolar spaces, and reductions in the endothelial lining of PAs, proliferative smooth muscle cells, fibroblasts, and adventitia. Moreover, BMP4 and TRPC1/4/6 expression increased to varying degrees in the arteries and lungs of smoking-exposed animals, whereas BMPR expression and SOCE increased only in the arteries, and PPAR-γ was downregulated in both the arteries and lungs. CONCLUSIONS: In SD rats, smoking exposure induces pulmonary vascular remodeling. The consequences of increased SOCE include increase in TRPC1/4/6, probably via augmented BMP4 expression, which also contribute to inflammatory responses in the lung. Moreover, interactions between BMP4 and PPAR-γ may play a role in preventing inflammation under normal physiological conditions.

5-Fluoro-1H-indole-3-carb-oxy-lic acid.

In the title compound, C(9)H(6)FNO(2), the carboxyl group is twisted slightly away from the indole-ring plane [dihedral angle = 7.39 (10)°]. In the crystal, carboxyl inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R(2) (2)(8) loops and N-H⋯O hydrogen bonds connect the dimers into (10[Formula: see text]) sheets.

[Association between social psychological factors and depressive symptoms among healthcare workers].

OBJECTIVE: To explore the association between the effort-reward imbalance at work and depressive symptoms among healthcare workers. METHODS: The effort-reward imbalance at work was conceptualized in terms of the Chinese version of the effort-reward imbalance (ERI) model. Depressive symptoms were assessed by the Chinese version of the Center of Epidemiology Survey Depression (CES-D) scale. The data came from the cross-sectional survey of 1 179 healthcare workers aged between 18 and 73 employed in 6 affiliated hospitals of Zhejiang University. The questionnaire comprised questions on the effort-reward at work, over-commitment, the full CES-D scale of depression and a range of other characteristics. Univariate analyses were used with Spearman's correlation, Mann-Whitney test, Pearson chi(2) test and likelihood chi(2) test. Multivariate logistic regression analyses was used to discover factors associated with depressive symptoms. RESULTS: The prevalence of depressive symptoms among healthcare workers was 48.12% (95% CI: 45.08% to 51.16%). The prevalence of depressive symptoms among nurses was 52.40% (95% CI: 47.87% to 56.93%) higher than doctors' 44.70% (95% CI: 10.64% to 48.77%) with the significant difference (chi(2) = 6.077, P = 0.014). Positive associations were found between the high effort-low reward, level of work-related over commitment and depressive symptoms (OR = 1.859, 95% CI: 1.337 to 2.585; OR = 2.207, 95% CI: 1.656 to 2.942) among healthcare workers, respectively. CONCLUSION: The high effort-low reward and the work-related over-commitment have a negative impact on healthcare workers' health.