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Background: It has been well documented that metabolic syndrome (MetS) increases severity of periodontitis. In this study, we determined the effect of high‐fat diet (HFD)‐induced MetS on alveolar bone loss in a mouse model with ligature‐induced periodontitis. To understand how MetS increases bone loss, we tested our hypothesis that palmitic acid (PA), a most abundant saturated fatty acid in the HFD, interacts with lipopolysaccharide (LPS) to promote osteoclastogenesis. Methods: We induced MetS by feeding mice HFD for 18 weeks and induced periodontitis with ligature placement. After treatments, we assessed alveolar bone loss using micro‐computed tomography and determined osteoclastogenesis using tartrate‐resistant acid phosphatase (TRAP) staining. To explore the mechanisms, we treated macrophages with PA, LPS or both and analyzed the osteoclast formation and cytokine expression in macrophages. Results: While ligature robustly induced periodontitis in mice with or without MetS, the mice with MetS had more bone loss than those without MetS. PA and LPS cooperatively induced osteoclast formation and stimulated the expression of inflammatory cytokines involved in osteoclastogenesis potentially via a FAT/CD36‐dependent mechanism in macrophages. Conclusions: HFD‐induced MetS increases alveolar bone loss in mice with ligature‐induced periodontitis, and PA and LPS cooperatively stimulate osteoclast formation and proinflammatory gene expression in macrophages. [ABSTRACT FROM AUTHOR]

Multiple factors such as genes, environment, and age are involved in developing Parkinson's disease (PD) pathology. However, how various factors interact to cause PD remains unclear. Here, 3-month and 9-month-old hα-syn+/- mice were treated with low-dose rotenone for 2 months to explore the mechanisms that underline the environment-gene-age interaction in the occurrence of PD. We have examined the behavior of mice and the PD-like pathologies of the brain and gut. The present results showed that impairments of the motor function and olfactory function were more serious in old hα-syn+/- mice with rotenone than that in young mice. The dopaminergic neuron loss in the SNc is more in old hα-syn+/- mice with rotenone than in young mice. Expression of hα-syn+/- is increased in the SNc of ha-syn+/- mice following rotenone treatment for 2 months. Furthermore, the number of activated microglia cells increased in SNc and accompanied the high expression of inflammatory cytokines, namely, TNF-α and IL-18 in the midbrain of old hα-syn+/- mice treated with rotenone. Meanwhile, we found that after treatment with rotenone, hα-syn positive particles deposited in the intestinal wall, intestinal microflora, and T lymphocyte subtypes of Peyer's patches changed, and intestinal mucosal permeability increased. Moreover, these phenomena were age-dependent. These findings suggested that rotenone aggravated the PD-like pathologies and affected the brain and gut of human a-syn+/- transgenic mice in an age-dependent manner. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of emodin on inflammation and autophagy in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages and reveal its underlying mechanism. Methods: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay was conducted to find the appropriate dose for emodin. RAW264.7 cells pretreated with different concentrations (0–50 μmol/L) of emodin or vehicle for 2 h prior to exposure to LPS for 16 h. Cell morphology was examined and propidium iodide staining was used to examine cell cycle. Expressions of inflammation-related proteins [nuclear factor-kappaB (NF-κ B) and I-kappaB (I κ B)α] and autophagy-related proteins [light chain (LC)3, P62/sequestosome 1, mammalian target of rapamycin (mTOR), and p-mTOR] were examined using Western blot analysis. Expression of inflammation-related cytokines including tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were detected by enzyme-linked immunosorbent assay. Autophagy was examined with LC3B fluorescence intensity and aggregation. The effect of emodin on autophagy was conducted with an autophagy inhibitor, 3-methyladenine (3-MA). Results: The expression of NF-κ B in LPS-induced cells was significantly increased (P<0.01) and simultaneously I κ B α decreased compared with the normal cell (P<0.05). The expressions of TNF-α, IL-β, and IL-6 proteins in the LPS-induced RAW264.7 cells were significantly higher than in the normal cell (P<0.05 or P<0.01). LPS increased the percentage of cells in the G0/G1 phase, which was recovered by emodin at different doses (12.5, 25, and 50μ mol/L, P<0.05 or P<0.01). The medium-dose (25 μ ml/L) emodin decreased the expressions of NF-κ B, P62 and p-mTOR (P<0.01) and increased I κ B α expression, LC3B II/I ratio as well as LC3B fluorescence intensity (P<0.05 or P<0.01). Meanwhile, the enhanced autophagic effects of emodin, such as the increment of LC3B II/ratio and the decrement of P62 expression, were suppressed by autophagy inhibitor 3-MA. Conclusion: Emodin could inhibit inflammation of mice RAW264.7 macrophages induced by LPS, possibly through activating autophagy. [ABSTRACT FROM AUTHOR]

A series of studies have confirmed that DNA methylation disorder (5mC/5hmC) is closely related to the occurrence and development of some diseases, such as Alzheimer's disease (AD). This study aims at discovering natural compounds that could adjust and control 5-hydroxymethylcytosine (5hmC) levels and improve Alzheimer's disease (AD) neuronal status. Cordycepin and cordycepic acid were selected as research materials, with resveratrol as positive control. The results of Dot Blot indicated that cordycepin, cordycepic acid, and resveratrol significantly increased the expression level of 5hmC. Combined with qPCR results, it was revealed that cordycepin increased the expression of ten-eleven translocation (TETs) mRNA compared with the abovementioned cordycepic acid and resveratrol. Besides, cordycepin dramatically reduced the transcription level of Apolipoprotein E (ApoE), suggesting that cordycepin might hinder the formation of NFTs (neurofibrillary tangles) and the accumulation of amyloid β-protein (Aβ) in the brain by reducing the expression of ApoE, resulting in affecting the progression of AD. Meanwhile, the immunofluorescence (IF) staining results demonstrated that the percentage of differentiation of SHSY-5Y cells reasonably increased after the treatment of cordycepin and cordycepic acid. Simultaneously, the length of axons and the number of dendritic branches in mouse primary neurons were substantially increased by cordycepin. The screening results illustrated that cordycepin had a positive influence on the level of 5hmC and the morphology of neurons, and most of the effects were better compared to the positive control (resveratrol). It indicated that cordycepin delayed the progression of neurodegenerative diseases such as AD. However, the specific mechanism of action still needs to be further investigated. Our research provided a foundation for further discussion about the influence of cordycepin on AD and a new idea for the pathological study of related diseases. [ABSTRACT FROM AUTHOR]