Chronic unpredictable stress-induced reproductive deficits were prevented by probiotics.

Stress can induce reproductive deficits by activating the HPA and causing oxidative stress. Some studies have indicated that the neurologic diseases or disorders induced by stress could be relieved by probiotics. Whether chronic unpredictable stress (CUS)-induced reproductive deficits could be prevented by probiotics is unclear. The present experiment was designed to evaluate the effects of L. rhamnosus Gorbach-Goldin (LGG) on CUS-induced reproductive deficits. Kunming mice were divided into control, stress, and LGG groups randomly. The mice in stress and LGG groups were exposed to CUS for 40days, in the meantime, the mice in LGG group were orally administered with LGG suspension at a dose of 0.3 mL/mouse (1×1010 cells/mL), and the mice in control and stress groups were orally administered with volume-equivalent sterile saline once a day. The results showed that the CUS-induced the sperm deficits including the count, motility, morphology, ultrastructure, DNA integrity, and chromatin condensation were protected by oral administration of LGG. In addition, the change of testosterone level induced by CUS was prevented by up-regulating the expressions of StAR and P450scc in the testes. Moreover, LGG could increase the activities of catalase, glutathione peroxidase, and superoxide dismutase significantly, and decrease the levels of oxidative products malondialdehyde and protein carbonyls significantly, as well as the levels of cyclooxygenase 2, interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α, to block the CUS-induced inflammatory response and the oxidative stress. The results indicated that the CUS-induced male reproductive deficits could be prevented by oral administration of LGG.

Reversal of ciprofloxacin-induced testosterone reduction by probiotic microbes in mouse testes.

CPFX is a highly effective antibiotic, but it has been reported to significantly impair both testicular function and structure in rats. In this study, we assessed reversal of CPFX-induced variation in mice testicular structure and testosterone synthesis by probiotic microbes in the infected model and normal model. We detected testicular weight, testicular structure and Leydig cell variables in numbers. We detected the levels of serum testosterone and steroidogenic enzymes, as well as DBC1, Sirt1, NF-κB, and related redox state and inflammatory response in the testes. The results showed that probiotic microbes had significantly elevated serum testosterone levels and steroidogenic enzymes, higher Sirt1, anti-oxidative enzymes and anti-inflammatory cytokine expression, and lower NF-κB, DBC1, oxidative damage, pro-inflammatory cytokine expression. The results suggest that the testis-protective, antiinflammatory and antioxidation effects of probiotics largely resulted from its ability to decrease oxidative stress and preserve antioxidant activity by stabilizing antioxidant defense systems, reducing oxidative damage and inflammatory response.

Chronic unpredictable stress abrogates the endotoxin tolerance induced by repeated peripheral LPS challenge via the TLR4 signaling pathway.

Endotoxin tolerance is induced by exposure to a repeated LPS challenge. Stress can exacerbate LPS-induced inflammation in the mouse hippocampus. However, the effects of stress on endotoxin tolerance have not been elucidated. The present experiments were designed to assess whether tolerance could be induced in the hippocampus by intraperitoneal injection of LPS at a dose of 250µg/kg for 7days, to investigate the effects of chronic unpredictable stress (CUS) on LPS-induced tolerance, and to assess underlying mechanisms in male Kunming mice. The levels of IL-1ß in the hippocampus increased to a plateau after 4days of LPS injection. When the CUS protocol was performed with concurrent LPS injections for 7days, body weight decreased, and IL-1ß expression in the hippocampus increased simultaneously. The expression of TLR4-MyD88-NF-κB signaling molecules and their negative regulators (PI3K, Akt) were also analyzed on day 7 after the last injection. The mRNA expression of TLR4 and MyD88 and the protein levels of TLR4 and NF-κBp65 were significantly increased, but the protein levels of PI3K and p-Akt were significantly decreased in the hippocampus of the mice. In conclusion, our findings show that endotoxin tolerance in the hippocampus was induced after four days of peripheral LPS challenge at a dose of 250µg/kg per day, and CUS abrogated this effect. CUS abolished endotoxin tolerance by reducing PI3K-mediated inhibition of TLR4-MyD88-NF-κB signaling pathways.

Various roles of astrocytes during recovery from repeated exposure to different doses of lipopolysaccharide.

Previous studies have demonstrated that the outcomes associated with neuroinflammation induced by intraperitoneal injection of lipopolysaccharide (LPS) at different dosages vary and either resolve or result in sepsis. The mechanisms underlying differential recoveries from varying doses of LPS are unclear. Additionally, changes in recovery involving chronic or continuous systemic inflammatory responses remain unclear. The present experiments were designed to evaluate the effects of systemic inflammation induced by repeated intraperitoneal injection of LPS at different doses on cognitive impairment. These experiments were also designed to investigate the roles of microglia and astrocytes in systemic inflammation and confirm the mechanisms that influence these processes. Kunming mice were given intraperitoneal injections of LPS at either 5mg/kg or 10mg/kg or saline for 7 consecutive days. Following the 7-day course of injections, a number of mice were kept undisturbed in their home cage for 30 days (30-day recovery), and other mice were similarly kept for 90 days (90-day recovery). The results revealed that the cognitive and physiological changes induced by 5mg/kg LPS included weight loss, impairments in spatial learning and memory, phenotypic changes in glia cells, and altered levels of pro-inflammatory cytokines; all of which were reversible. A potential recovery mechanism involves a neuroprotective function of activated astrocytes that secreted glial-derived neurotrophic factor (GDNF) following 30-day recovery. The changes induced by 10mg/kg LPS included weight loss, phenotypic changes in glia cells, and altered levels of pro-inflammatory cytokines were also reversible; however, a longer recovery was required (90 days). Although 10mg/kg LPS-induced neuroinflammation was reversible, the associated impairments in spatial learning and memory were permanent. A potential mechanism underlying permanent damage associated with 10mg/kg LPS involves the role of the activated astrocytes changing from neuroprotection to destruction, which is mediated by increased pro-inflammatory cytokines in more serious neuroinflammation.

Effects of moderate exercise over different phases on age-related physiological dysfunction in testes of SAMP8 mice.

Oxidative stress and chronic inflammation have been implicated in the testicular aging process. Different types and moderate-intensity of regular exercise may reduce age-related physiological dysfunction associated with inflammation and oxidative stress, but such effects of moderate-intensity of exercise over different phases of life in testes have not been reported. In this study, male SAMP8 mice, a senescence-accelerated strain, were maintained as sedentary (sed) or subjected to daily 15-min periods of swimming exercise between ages of 2-7 months (lifelong), 2-4 months (earlier) or 5-7 months (late). Age-related changes, including serum testosterone levels and biomarkers of inflammation and oxidative stress were analyzed at the end of the experiment. All exercise groups showed significantly greater serum testosterone levels and decreased age-related inflammation and oxidative stress compared with the sedentary group. Exercise also increased expression and activity of the nuclear factor erythroid 2-related factor (Nrf2), a transcriptional regulator of the cellular anti-oxidant system, and decreased expression and activity of nuclear factor kappa beta (NF-κB), a mediator of inflammatory molecules, in the nucleus of testicular cells. However, lifelong and earlier groups generally showed significantly better protective effects than the late group against age-related physiological dysfunction in testes. Thus, lifelong exercise and earlier phase exercise were most effective in counteracting oxidative stress and inflammation and in preserving testes function through regulation of Nrf2 and NF-κB. These results advocate the benefits of lifelong exercise and emphasize a greater protection against male aging by instituting exercise earlier rather than late in life.

Programming of regulatory T cells from pluripotent stem cells and prevention of autoimmunity.

Regulatory T (Treg) cells are being used to treat autoimmunity and prevent organ rejection; however, Treg cell-based therapies have been hampered by the technical limitation in obtaining a high number of functional Treg cells. In this study, we show how to generate functional Treg cells from induced pluripotent stem (iPS) cells and to determine the potential role of such cells for Treg cell-based immunotherapy against autoimmunity in a therapeutic setting. Ligation of a Notch ligand and transduction of the gene Foxp3 induce iPS cells to differentiate into Treg cells. Expression of Foxp3 and coculture on Notch ligand-expressing stromal cells augment expression of CD3, TCR, CD4, CD25, and CTLA-4 on iPS cell-differentiated Treg cells, which are able to secrete TGF-ß and IL-10 both in vivo and in vitro. Importantly, adoptive transfer of iPS cell-derived Treg cells expressing large amounts of Foxp3 and Bcl-x(L) significantly suppresses host immune responses and reduces arthritis development within murine models. These data suggest that Notch signaling and Foxp3 regulate the development and function of Treg cells derived from iPS cells. Our results provide a novel approach for generating potentially therapeutic Treg cells for the treatment of autoimmune diseases.

Learning, memory, and glial cell changes following recovery from chronic unpredictable stress.

Previous research has indicated that chronic stress induces inflammatory responses, cognitive impairments, and changes in microglia and astrocytes. However, whether stress-induced changes following recovery are reversible is unclear. The present study examined the effects of chronic unpredictable stress (CUS) following recovery on spatial learning and memory impairments, changes in microglia and astrocytes, and interleukine-1ß (IL-1ß) and glial-derived neurotrophic factor (GDNF) levels. Mice were randomly divided into control, stress, and recovery groups, and CUS was applied to mice in the stress and recovery groups for 40 days. Following the application of CUS, the recovery group was allowed 40 days without stress. The results of the Morris water maze illustrated that CUS-induced spatial learning and memory impairments could be reversed or even improved by a period of recovery. Immunohistochemical tests revealed that CUS-induced alterations in microglia could dissipate with time in the CA3 region of the hippocampus and prelimbic areas. However, CUS-induced activation of astrocytes was sustained in the CA3 area following recovery. Western blot analyses revealed that CUS induced a significant increase of GDNF and a significant decrease in IL-1ß. Additionally, increased GDNF levels were sustained in the hippocampus during recovery. In conclusion, this study provides evidence that CUS-induced learning and memory impairments could be reversible following recovery. However, activated astrocytes and increased GDNF levels in the hippocampus remained elevated after recovery, suggesting that activated astrocytes and increased GDNF play important roles in the adaptation of the brain to CUS and in repairing CUS-induced impairments during recovery.

[Construction of recombinant BCG bearing S1 glycoprotein of nephropathogenic IBV and study on its immunogenicity on chickens].

Glycoprotein Si was the major protein to determine infection and immunogenicity of Infectious bronchitis virus (IBV). The S1 glycoprotein gene of IBV isolates were amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) and proved to be S1 gene by sequencing. The E. coli-mycobacterium expression shuttle plasmid pR-alpha-S1 was constructed by inserting the S1 gene to the pRR3 with human mycobacterium tuberculosis HSP70 promoter and a signal peptide. Then the plasmid pR-alpha-S1 was introduced into mycobacterium bovis BCG by electroporation to construct a recombinate strain rBCG-Sl. The S1 protein could be highly expressed in M. smegmatis mc2 155 when induced by heating and was detected by ELISA and Western blot assays using monoclonal antibody against S1 glycoprotein of IBV. 6 week-old SPF chicken were subcutaneously immunized with 10(6) cfu rBCG-S1 and each chick was immunized three times at 3 week intervals with the same antigen used for the primary immunization. The protective immunity of rBCG-S1 was identified in vaccinated chickens. Results from the protection test showed the two immunizations with rBCG-S1 could provide protection for chickens from the challenge with virulent nephropathogenic IBV strain X. Haemagglutination inhibition titers were also increased in chickens immunized with the expressed rBCG-S1, and significantly higher titers were detected after challenge. These data indicate that the rBCG-S1 could be used as candidate of a live vector vaccine for NIBV.