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Macrophages can initiate innate immune responses against microbes and cancer. The aim of this study was to elucidate the effects of Brassica rapa L. on macrophages. The production of interleukin (IL)-6, tumor necrosis factor (TNF)-α, and interferon-γ induced by the insoluble fraction of B. rapa L. was decreased in macrophage-depleted spleen cells compared with controls. The insoluble fraction of B. rapa L. induced expression of H-2Kb, I-Ab, CD40, and CD86, production of cytokines and nitric oxide, and phagocytic activity in RAW264 cells. After treatment with the insoluble fraction, IL-6 and TNF-α production was significantly decreased by anti-Toll-like receptor (TLR)2 mAb or polymyxin B compared with the control. Furthermore, insoluble fraction-mediated cytokine production was significantly lower in peritoneal macrophages from TLR2−/− and TLR4−/− mice compared with wild-type mice. These results suggest that B. rapa L. is a potentially effective immunomodulator for activating macrophages to prevent infections. [ABSTRACT FROM AUTHOR]

• Procyanidin, which has gallate groups, suppresses production of TNF-α and IFN-γ. • Procyanidin gallate regulates glycolytic activity of CD4+ T cells. • Suppression of cytokine production is mediated by the mTOR-HIF-1 pathway. • Posttranscriptional control of TNF-α mRNA is regulated by procyanidin gallate. Procyanidins are polyphenols with antioxidant, anti-obesity, and anti-inflammatory properties. Procyanidin B2 (PCB2) gallate; specifically, PCB2 3,3″-di-O-gallate (PCB2DG), inhibits cytokine production in T cells. However, the molecular interactions and partners of PCB2DG underlying this suppression of cytokine production are unclear. The present study aimed to elucidate mechanisms underlying regulation of tumor necrosis factor (TNF)-α production by PCB2DG. We found that production of TNF-α and glycolytic activity in activated CD4+ T cells were suppressed by PCB2DG treatment. The inhibition of TNF-α production was found to be mediated by mammalian target of rapamycin (mTOR) and hypoxia inducible factor 1 (HIF-1) pathway, as PCB2DG suppressed the expression of HIF-1α, p-mTOR, and p-p70S6K (a downstream of the mTOR complex, mTORC1). Moreover, suppression of TNF-α production was mediated by regulation of the glycolytic enzyme lactate dehydrogenase at the posttranscriptional level. These results suggest that PCB2DG regulates TNF-α production by inhibiting glycolytic activity via the mTOR-HIF-1 pathway. [ABSTRACT FROM AUTHOR]

• Caloric restriction modulates immune cells and cytokine expression. • Circulating miR-16-5p is upregulated in calorie-restricted mice. • The expression of inflammatory cytokines is downregulated by miR-16-5p. Caloric restriction (CR) has long been known to increase median and maximal lifespans and to decrease mortality and morbidity in short-lived animal models, likely by altering fundamental biological processes that regulate aging and longevity. However, the detailed mechanisms of immunomodulation by CR remain unclear. In this study, we established a mouse model for CR and analyzed the changes of immune cells in these mice. The CR mice fed a calorie-restricted diet for 4 weeks had lower body weight and fat mass compared with control mice. The proportions of CD4+, CD8+, and naïve CD4+ T cells in spleen cells from CR mice were higher than those in of control mice. Additionally, the proportion of CD8+ T cells was significantly decreased and the mRNA expression of proinflammatory cytokines in the colon of CR mice was significantly decreased compared with those of control mice. To determine the effect of CR on microRNA (miRNA) expression, serum and tissues were collected from mice and the expression level of miRNA was analyzed by real-time RT-PCR. As a result, the expressions of miR-16-5p, miR-196b-5p, and miR-218-5p in serum from CR mice were higher than those in control mice. The expression of miR-16-5p increased in the spleen, thymus, colon, and stomach of CR mice compared with expression in control mice. Furthermore, RAW264 cells transfected with a miR-16-5p mimic significantly decreased the mRNA expression of IL-1β, IL-6, and TNF-α under LPS stimulation. These results suggested that miR-16-5p might be a critical factor involving the anti-inflammatory effects of calorie-restricted feeding. [ABSTRACT FROM AUTHOR]

Aging is associated with a decrease in the function of the immune system, a phenomenon known as immunosenescence, which results in reduced resistance to infection. Caloric restriction (CR) is known to prolong lifespan and to regulate immune function. However, whether and how CR affects immunosenescence remains unclear. Here, we evaluated the effect of long- and short-term CR on immunosenescence by subjecting wild-type mice to CR between 6 and 18 months of age or between 17 and 18 months of age, respectively. Compared with a normal diet or short-term CR, long-term CR induced marked or complete attenuation of age-related decreases in the frequency of spleen NK cells and NKT cells; naïve CD4 + and CD8 + T cells; and cytokine- and granzyme B-secreting T cells. In contrast, both long- and short-term CR significantly suppressed age-related upregulation of the T cell exhaustion markers PD-1, Tim-3, and KLRG1, as well as the transcription factors NR4A1 and TOX, which regulate the expression of genes associated with the T cell exhaustion phenotype. These results suggest that CR might suppress age-associated immunosenescence by regulating the expression of transcription factors and target genes that control T cell exhaustion., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Linear accelerator-based radiotherapy has little effect on tumors such as malignant melanoma, various types of sarcoma, and most locally-advanced neoplasms that have grown to several centimeters or more. These tumors contain many hypoxic cancer cells or large amounts of anti-oxidative enzymes, and are therefore resistant to low linear energy transfer radiation. Therefore, it was necessary to develop a new radiosensitizer to overcome these situations. We previously developed a new enzyme-targeting radiosensitization treatment named KORTUC I, which uses 3% w/v hydrogen peroxide solution-soaked gauze. We developed a new radiosensitizer for intratumoral injection (KORTUC II), comprising a combination of hydrogen peroxide and sodium hyaluronate. After providing a fully informed written consent, 52 patients with unresectable or recurrent neoplasms (53 lesions) were enrolled in the KORTUC II trial. The present study of 52 patients with unresectable or recurrent neoplasms showed that KORTUC II is safe when injected intratumorally, well tolerated, and can efficiently exert a radiation sensitizing effect. Because this radiosensitizer is safe and less expensive than other methods, and can be applied for almost every type of low-LET radio-resistant neoplasm, it has potential for worldwide and immediate use.