Taurine Alleviates Experimental Colitis by Enhancing Intestinal Barrier Function and Inhibiting Inflammatory Response through TLR4/NF-κB Signaling.

Taurine (Tau) is a semiessential amino acid in mammals with preventive and therapeutic effects on several intestinal disorders. However, the exact function of taurine in ulcerative colitis (UC) is still largely unclear. In this study, we used two taurine-deficient mouse models (CSAD-/- and TauT-/- mice) to explore the influence of taurine on the progression of UC in both dextran sulfate sodium (DSS)-induced colitis and LPS-stimulated Caco-2 cells. We found that cysteine sulfinic acid decarboxylase (CSAD) and taurine transporter (TauT) expressions and taurine levels were markedly reduced in colonic tissues of mice treated with DSS. The CSAD and TauT knockouts exacerbated DSS-induced clinical symptoms and pathological damage and aggravated the intestinal barrier dysfunction and the colonic mucosal inflammatory response. Conversely, taurine pretreatment enhanced the intestinal barrier functions by increasing goblet cells and upregulating tight junction protein expression. Importantly, taurine bound with TLR4 and inhibited the TLR4/NF-κB pathway, ultimately reducing proinflammatory factors (TNF-α and IL-6) and oxidative stress. Our findings highlight the essential role of taurine in maintaining the intestinal barrier integrity and inhibiting intestinal inflammation, indicating that taurine is a promising supplement for colitis treatment.

Intestinal melatonin levels and gut microbiota homeostasis are independent of the pineal gland in pigs.

Introduction: Melatonin (MEL) is a crucial neuroendocrine hormone primarily produced by the pineal gland. Pinealectomy (PINX) has been performed on an endogenous MEL deficiency model to investigate the functions of pineal MEL and its relationship with various diseases. However, the effect of PINX on the gastrointestinal tract (GIT) MEL levels and gut microbiome in pigs has not been previously reported. Methods: By using a newly established pig PINX model, we detected the levels of MEL in the GIT by liquid chromatography-tandem mass spectrometry. In addition, we examined the effects of PINX on the expression of MEL synthesis enzymes, intestinal histomorphology, and the intestinal barrier. Furthermore, 16S rRNA sequencing was performed to analyze the colonic microbiome. Results: PINX reduced serum MEL levels but did not affect GIT MEL levels. Conversely, MEL supplementation increased MEL levels in the GIT and intestinal contents. Neither PINX nor MEL supplementation had any effect on weight gain, organ coefficient, serum biochemical indexes, or MEL synthetase arylalkylamine N-acetyltransferase (AANAT) expression in the duodenum, ileum, and colon. Furthermore, no significant differences were observed in the intestinal morphology or intestinal mucosal barrier function due to the treatments. Additionally, 16S rRNA sequencing revealed that PINX had no significant impact on the composition of the intestinal microbiota. Nevertheless, MEL supplementation decreased the abundance of Fibrobacterota and increased the abundance of Actinobacteriota, Desulfobacterota, and Chloroflexi. Conclusion: We demonstrated that synthesis of MEL in the GIT is independent of the pineal gland. PINX had no influence on intestinal MEL level and microbiota composition in pigs, while exogenous MEL alters the structure of the gut microbiota.

CK1α deficiency impairs mouse uterine adenogenesis by inducing epithelial cell apoptosis through GSK3ß pathway and inhibiting Foxa2 expression through p53 pathway†.

Uterine glands and their secretions are crucial for conceptus survival and implantation in rodents and humans. In mice, the development of uterine gland known as adenogenesis occurs after birth, whereas the adenogenesis in humans initiates from fetal life and completed at puberty. Uterine adenogenesis involves dynamic epithelial cell proliferation, differentiation, and apoptosis. However, it is largely unexplored about the mechanisms governing adenogenesis. CK1α plays important roles in regulating cell division, differentiation, and death, but it is unknown whether CK1α affects adenogenesis. In the current study, uterus-specific CK1α knockout female mice (Csnk1a1d/d) were infertile resulted from lack of uterine glands. Subsequent analysis revealed that CK1α deletion induced massive apoptosis in uterine epithelium by activating GSK3ß, which was confirmed by injections of GSK3ß inhibitor SB216763 to Csnk1a1d/d females, and the co-treatment of SB216763 and CK1 inhibitor d4476 on cultured epithelial cells. Another important finding was that our results revealed CK1α deficiency activated p53, which then blocked the expression of Foxa2, an important factor for glandular epithelium development and function. This was confirmed by that Foxa2 expression level was elevated in p53 inhibitor pifithrin-α injected Csnk1a1d/d mouse uterus and in vitro dual-luciferase reporter assay between p53 and Foxa2. Collectively, these studies reveal that CK1α is a novel factor regulating uterine adenogenesis by inhibiting epithelial cell apoptosis through GSK3ß pathway and regulating Foxa2 expression through p53 pathway. Uncovering the mechanisms of uterine adenogenesis is expected to improve pregnancy success in humans and other mammals.

Casein Kinase 1α Regulates Testosterone Synthesis and Testis Development in Adult Mice.

Casein kinase 1α (CK1α) is a main component of the Wnt/ß-catenin signaling pathway, which participates in multiple biological processes. Our recent study demonstrated that CK1α is expressed in both germ cells and somatic cells of mouse testes and regulates spermatogenesis. However, little information is known about the role of CK1α in regulating the development of somatic cells in mouse testes. Our results demonstrated that conditional disruption of CK1α in murine Leydig cells sharply decreased testosterone levels; markedly affected testis development, sperm motility, and sperm morphology; and caused subfertility. The germ cell population was partially decreased in CK1α conditional knockout (cKO) mice, while the proliferation of Leydig cells and Sertoli cells was not affected. Furthermore, in vitro results verified that luteinizing hormone upregulates CK1α through the luteinizing hormone/protein kinase/Epidermal Growth Factor Receptor/extracellular regulated protein kinases/2 signaling pathway and that CK1α interacts with and phosphorylates EGFR, which subsequently activates the phosphorylation of ERK1/2, thereby promoting testosterone synthesis. In addition, high-dose testosterone propionate partially rescued the phenotype observed in cKO mice. This study provides new insights into the role of CK1α in steroidogenesis and male reproduction.

Hepatoprotective Effects of Taurine Against Cadmium-Induced Liver Injury in Female Mice.

Cadmium (Cd), a heavy metal contaminant, seriously threatens human and animal health. Taurine (Tau) has been used against hepatotoxicity caused by different environmental toxins. However, it has not been elucidated whether Tau exerts its protective function against Cd-induced hepatotoxicity. The aim of this study was thus to evaluate the ameliorative function of Tau (500 mg/kg body weight intraperitoneally) on Cd-induced (2 mg/kg body weight intraperitoneally) liver toxicity in mice for 14 days. The histopathologic and ultrastructure changes as well as alterations in indexes related to liver function, antioxidant biomarkers, inflammatory, and apoptosis were evaluated. The results showed that Tau alleviated the vacuolar degeneration, nuclear condensation, mitochondria swelling, and cristae lysis of hepatocytes induced by Cd. In addition, Tau treatment significantly reduced the ALT, AST levels in serum, and inflammatory factor TNF-α and IL-1ß in liver tissue. Furthermore, Tau treatment decreased the Bax/Bcl-2 ratio and cleaved caspase-3 protein expression levels. Taken together, these observations demonstrate that Tau has an important hepatic protective function against the inflammation and apoptosis induced by Cd.

Oocyte Casein kinase 1α deletion causes defects in primordial follicle formation and oocyte loss by impairing oocyte meiosis and enhancing autophagy in developing mouse ovary.

Casein kinase 1α is a member of CK1 family, which is ubiquitously expressed and plays multiple functions, including its potential roles in regulating cell division. But the functions of CK1α in mammalian oogenesis and folliculogenesis remain elusive. In this study, we assayed the cell type of CK1α expression in the developing mouse ovary and confirmed that CK1α was highly expressed in ovaries after birth. The oocyte-specific CK1α knockout (cKO) mouse model was then established by crossing Ddx4-Cre mice with Csnk1a1-floxp mice, and the effects of CK1α deletion on oogenesis and folliculogenesis were identified. The results showed that oocyte CK1α deletion impaired the progression of oocyte meiosis and primordial follicle formation during meiotic prophase I, which subsequently caused oocyte loss and mouse infertility. Further, the in vivo CK1α deletion and in vitro inhibition of CK1 activity resulted in the defects of DNA double-strand break (DSB) repair, whereas apoptosis and autophagy were enhanced in the developing ovary. These may contribute to oocyte loss and infertility in cKO mice. It is thus concluded that CK1α is essential for mouse oogenesis and folliculogenesis by involving in regulating the processes of oocyte meiosis and DNA DSB repair during meiotic prophase I of mouse oocytes. However, the related signaling pathway and molecular mechanisms need to be elucidated further.

MicroRNA-7a2 is Required for the Development of Pituitary Stem Cells.

The pituitary gland is inhabited by a subpopulation of SOX2+ stem cells. However, the regulatory mechanisms underlying pituitary stem cell development remain poorly understood. In this study, we demonstrate that microRNA-7a (miR-7a) is enriched in the developing pituitary and is spatiotemporally expressed in the pituitary stem cells. Constitutive deletion of mir-7a2 in mice results in pituitary dysplasia emerging during birth, which is primarily manifested as malformed anterior lobes. Using immunofluorescence, immunohistochemistry, or in situ hybridization, we observe that the specification of hormone-expressing cells is not impeded post mir-7a2 deletion at birth, although the terminal differentiation of gonadotropes is inhibited. Further investigation of neonatal and adult pituitaries in mir-7a2 knockout mice reveals an expansion of the SOX2+ pituitary stem cell compartment. The inhibition of epithelial-mesenchymal like transition seems to be responsible for this phenotype, rather than abnormal proliferation or apoptosis. Furthermore, our data suggest that Gli3 and Ckap4 are potential targets of miR-7a in pituitary stem cells. In summary, our results identify miR-7a2 as a crucial factor involved in pituitary stem cell development.

Taurine Has Potential Protective Effects against the Chronic Cardiotoxicity Induced by Doxorubicin in Mice.

Doxorubicin (DOX) is an effective anticancer anthracycline drug; however, the cardiotoxicity limits its application. The aim of the present study was to investigate the potential protective effect of taurine against DOX-induced chronic cardiotoxicity in mice. We found that exogenous supplementation of taurine can inhibit the weight loss of mice caused by DOX. The increased activity of myocardial enzymes creatine kinase (CK) and lactate dehydrogenase (LDH) in response to DOX treatment were significantly hampered. In addition, taurine supplementation alleviated the decrease in superoxide dismutase (SOD) activity, glutathione (GSH) content, glutathione peroxidase 4 (Gpx4) expression, and the increase in malondialdehyde (MDA) content caused by DOX. Besides, taurine alleviated myocardial myofibrillar disruption and mitochondrial edema. Furthermore, our results showed that taurine decreased the expressions of cleaved caspase-3 and Bax/Bcl2, thereby inhibiting apoptosis. These collective data demonstrated that exogenous taurine supplementation has a potentially protective effect against the myocardial damage caused by doxorubicin in mice by enhancing antioxidant capacity and reducing oxidative damage and apoptosis.

MicroRNA-7a inhibits Isl1 expression to regulate insulin secretion by targeting Raf1 and Mapkap1 in NIT-1 cells.

Both microRNA-7a (miR-7a) and LIM-homeodomain transcription factor ISL1 are important factors regulating insulin transcription and secretion, but the functional relationship and the interacting mechanisms between miR-7a and ISL1 in pancreatic islet ß-cells remain unknown. The aims of this study were thus to identify the potential interactions and signaling communication between miR-7a and ISL1 in regulating insulin transcription and secretion in the cultured NIT-1 cells. The results show that miR-7a inhibitor upregulates Isl-1 and insulin gene expressions, and the insulin secretion. Whereas miR-7a mimics inhibit ISL1 and insulin gene expressions, and decreases the insulin secretion. Furthermore, we identified the target gene of miR-7a using dual-luciferase reporter assay, and the results demonstrate that Raf1 and Mapkap1 is a direct target gene of miR-7a, modeling RAF1/MEK/ERK1/2 and mTORC2/AKT signaling pathway to regulate Isl1 expression, and thus influencing insulin expression and secretion. Our results indicate that therapeutic inhibition of miR-7a function could be of relevance for preserving the function of pancreatic ß-cells during the course of diabetes development, implicating miR-7, ISL1, and/or the connecting molecules may act as novel targets for pharmacological or gene therapy in diabetes and related metabolic disease, although much detailed studies are required in the further study.

Respiratory syncytial virus infection in children and its correlation with climatic and environmental factors.

OBJECTIVE: In this study, we aimed to investigate the clinical epidemiology of lower respiratory tract infections with different respiratory syncytial virus (RSV) subtypes in hospitalized children in Suzhou and their correlation with climatic and environmental factors. METHOD: In this retrospective cross-sectional study, we collected nasopharyngeal secretion samples from children hospitalized with acute lower respiratory tract infection. We collected the clinical data of children with RSV infection, and compared and analyzed their epidemiological characteristics. RESULTS: RSV-B was the dominant strain in 2016. In 2018, RSV-A was the dominant strain. The positive detection rate of RSV-A was negatively correlated with monthly mean temperature, monthly mean wind speed, total monthly rainfall, and O3 concentration and positively correlated with PM2.5, PM10, and NO2, SO2, and CO concentrations. The positive detection rate of RSV-B was negatively correlated with monthly average temperature, monthly total rainfall, monthly sunshine duration, and O3 concentration and positively correlated with CO concentration. CONCLUSIONS: RSV-A was the main subtype detected in this study. The positive detection rate of RSV-A was related to temperature, wind speed, rainfall, PM2.5. PM10, and NO2, SO2, CO, and O3 concentrations. The positive detection rate of RSV-B was related to temperature, rainfall, sunshine time, and O3 concentration.

Zearalenone affects reproductive functions of male offspring via transgenerational cytotoxicity on spermatogonia in mouse.

Previous studies have demonstrated that Zearalenone (ZEA) affects not only maternal reproductive function but also that of the offspring. However, the transgenerational toxic effects of ZEA on the spermatogonia of male F1 mice are not clear. The present study was thus designed to determine whether the fertility of male F1 mice was affected following exposure of F0 pregnant mice to ZEA. In present study, 32 pregnant female mice were divided into 4 groups and exposed to ZEA of 0, 2.5 and 5.0 mg/kg, respectively, and the testis development and reproductive performance of 96 male F1 mice were analyzed. The results demonstrated that the F0 pregnant mice treated with ZEA resulted in increased anogenital distances in the newborn male F1 mice. Moreover, ZEA caused abnormal vacuole structures and loose connections in the testes of male F1 offspring, compared with the controls. Further ultramicrostructural analysis showed that the mitochondria appeared to be vacuolated with ablated membranes and cristae, and this was accompanied by the presence of large lipid droplets in the spermatogonia. Further, the semen quality and sperm counts declined significantly, and increased malformation rates and decreased testosterone levels were observed in the male F1 offspring from experimental groups. Our results reveal the toxic effects of ZEA on F0 pregnant mice is transgenerational, and affects the fertility of male F1 mice by damaging the spermatogonial cells. This offers a new viewpoint of ZEA-induced reproductive toxicity in male animals and provides a new potential direction for the treatment and prevention of ZEA-induced cytotoxicity.

MicroRNA-7 inhibits melatonin synthesis by acting as a linking molecule between leptin and norepinephrine signaling pathways in pig pineal gland.

MicroRNAs, including microRNA-7 (miR-7), are important modulators of numerous gene expressions and the related biological processes. Melatonin is a key hormone regulating daily and seasonal rhythms, in which a variety of positive and negative regulatory factors, such as norepinephrine (NE) and leptin, are involved. However, the interactions among these factors and the mechanisms remain to be elucidated. The aims of the present study were to identify the functions and the related mechanisms of miR-7 in regulating melatonin synthesis and secretion through in vitro and in vivo experiments in pineal gland of pigs, which is an important animal model for agricultural and biomedical studies. Our results firstly show that miR-7 is specifically expressed in porcine pinealocytes and negatively regulates melatonin synthesis. The further functional studies show that the dynamic expression levels of miR-7 are contrary to the melatonin levels throughout the day, and the forced inhibition of endogenous miR-7 in porcine pinealocytes sharply increases arylalkylamine N-acetyltransferase (AANAT) expression by 80.0% (P = 0.0031) and melatonin levels by 81.0% (P = 0.0421), whereas miR-7 over-expression down-regulates AANAT expression by 38.6% (P = 0.0004) and melatonin levels by 37.6% (P = 0.0212). In addition, the miR-7 expression is up-regulated by leptin through the JAK/STAT3 signaling pathway, and the in vivo intracerebroventricular injection of leptin increases miR-7 expression by 80.0% (P = 0.0044) in porcine pineal glands and reduces melatonin levels by 57.1% (P = 0.0060) compared with the controls. This functional inhibition of melatonin synthesis by miR-7 is accomplished by its binding to the 3'-UTR of Raf1. Further, our results demonstrate that the RAF1/MEK/ERK signaling pathway mediates NE-induced AANAT expression, whereas leptin attenuates NE's function through miR-7. Taken together, the results demonstrated that leptin activates the JAK/STAT3 signaling pathway to increase the expression of miR-7, which acts as a negative regulatory molecule inhibiting NE-activated RAF1/MEK/ERK signaling pathway by targeting Raf1, resulting in decreased AANAT expression and melatonin synthesis. These findings suggest that miR-7 is a novel negative regulator of melatonin synthesis and links leptin- and NE-mediated signaling pathways in porcine pineal glands, which will contribute to our understanding in the establishment of the biological rhythms resulting from melatonin.

LIM homeobox transcription factor Isl1 is required for melatonin synthesis in the pig pineal gland.

Melatonin is a key hormone that regulates circadian rhythms, metabolism, and reproduction. However, the mechanisms of melatonin synthesis and secretion have not been fully defined. The purpose of this study was to investigate the functions of the LIM homeobox transcription factor Isl1 in regulating melatonin synthesis and secretion in porcine pineal gland. We found that Isl1 is highly expressed in the melatonin-producing cells in the porcine pineal gland. Further functional studies demonstrate that Isl1 knockdown in cultured primary porcine pinealocytes results in the decline of melatonin and arylalkylamine N-acetyltransferase (AANAT) mRNA levels by 29.2% and 72.2%, respectively, whereas Isl1 overexpression raised by 1.3-fold and 2.7-fold. In addition, the enhancing effect of norepinephrine (NE) on melatonin synthesis was abolished by Isl1 knockdown. The in vivo intracerebroventricular NE injections upregulate Isl1 mRNA and protein levels by about threefold and 4.5-fold in the porcine pineal gland. We then examined the changes in Isl1 expression in the pineal gland and global melatonin levels throughout the day. The results show that Isl1 protein level at 24:00 is 2.5-fold higher than that at 12:00, which is parallel to melatonin levels. We further found that Isl1 increases the activity of AANAT promoter, and the effect of NE on Isl1 expression was blocked by an ERK inhibitor. Collectively, the results presented here demonstrate that Isl1 positively modulates melatonin synthesis by targeting AANAT, via the ERK signaling pathway of NE. These suggest that Isl1 plays important roles in maintaining the daily circadian rhythm.

A prospective, randomized, controlled study of a suspension positioning system used with elderly bedridden patients with neurogenic fecal incontinence.

Elderly patients with acute neurological impairment are prone to severe disability, fecal incontinence (FI), and resultant complications. A suspension positioning system (SPS), based on the orthopedic suspension traction system commonly used for conservative treatment of pediatric femoral fracture and uncomplicated adult pelvic fracture, was developed to facilitate FI management in patients immobilized secondary to an acute neurological condition. To evaluate the effectiveness and safety of the system, a prospective, randomized, controlled study was conducted between October 2009 and July 2012. Two hundred (200) elderly, bedridden, hospitalized patients with acute, nonchronic neurological impairment were randomly assigned to receive routine FI nursing care (ie, individualized dietary modification, psychological support, health education, and social support for caregivers and family members [control group]) or routine incontinence care plus the SPS (experimental group) during the day. Rates of perianal fecal contamination, skin breakdown, incontinence associated dermatitis, pressure ulcer development, and lower urinary tract infection (LUTI) were significantly lower in the SPS than in the control group (P <0.05). Length of hospitalization and costs of care were also lower in the SPS group (P <0.05). Patient quality-of-life (QoL) and FI QoL scores were similar at baseline but significantly higher (better) at the 6-month follow-up interview in the SPS than in the control group (P <0.05). In this study, the rate of FI-associated morbidities was lower and 6-month patient QoL scores were higher in the SPS than in the control group. No adverse events were observed, and all patients completed the study. Further clinical studies are needed to examine the long-term effects of SPS use among neurologically impaired FI patients.