Effects of Hormone Therapy and Flavonoids Capable on Reversal of Menopausal Immune Senescence.

Menopause, probably the most important natural change in a woman's life and a major component of female senescence, is characterized, inter alia, by cessation of ovarian estrogen and progesterone production, resulting in a gradual deterioration of the female immune system. Hormone replacement therapy (HRT) is used in postmenopausal women to relieve some of the peri- and postmenopausal symptoms, while there is also evidence that the therapy may additionally partially reverse menopausal immune senescence. Flavonoids, and especially isoflavones, are widely used for the treatment of menopausal symptoms, although it is not at present clear whether they can reverse or alleviate other menopausal changes. HRT reverses the menopausal CD4/CD8 ratio and also limits the general peri- and postmenopausal inflammatory state. Moreover, the increased levels of interleukins (IL)-1ß, IL-6, and IL-8, as well as of tumor necrosis factor-α (TNF-α) are decreased after the initiation of HRT. However, some reports show no effect of HRT on IL-4, IL-10, and IL-12. It is thus evident that the molecular pathways connecting HRT and female immune senescence need to be clarified. Interestingly, recent studies have suggested that the anti-inflammatory properties of isoflavones possibly interact with inflammatory cytokines when applied in menopause treatments, thereby potentially reversing immune senescence. This narrative review presents the latest data on the effect of menopausal therapies, including administration of flavonoid-rich products, on age-associated immune senescence reversal with the aim of revealing possible directions for future research and treatment development.

The paradigm of immunosenescence in atherosclerosis-cardiovascular disease (ASCVD).

The new immunosenescence paradigm (2015) was an attempt to explain a mechanism by which macrophages could be immunosuppressed and dysfunctional, yet paradoxically release proinflammatory factors in an unregulated manner. This mechanism was linked to the loss of dehydroepiandrosterone (DHEA) with aging and thus explained how immunosenescence could be causally related to the risk of stress and/or age-associated chronic diseases. At the center of this paradigm was lipid body negative (LB-) foamy macrophage (CD14+CD16+) which produced human endogenous retrovirus K102 (HERV-K102) particles. HERV-K102 may be a protector foamy virus of humans, and its induction may generate trained innate immunity, a special type of autoimmunity, in response to intracellular pathogens, their constituents, toxins, and/or tumors. Overwhelming evidence now suggests that the proinflammatory foamy macrophages driving ASCVD are LB-. Moreover, the monocyte/macrophage phenotype implicated in atherosclerosis-cardiovascular disease (ASCVD) appears to be the CD14+CD16+ intermediate phenotype. These and other observations directly challenge the cholesterol hypothesis. For the prevention and treatment of ASCVD, it is important to address the putative cause of ASCVD -- immunosenescence, rather than the signs or symptoms such as inflammation or elevated cholesterol. Therefore, strategies to reverse or prevent immunosenescence, which improve or maintain an optimal cortisol/DHEA ratio such as isoflavonoids, would be expected to alleviate not only ASCVD but the risk of many other age-associated chronic diseases. Here, the new immunosenescence paradigm will be appraised for its suitability to explain ASCVD risks.

Regulatory Effect of Anwulignan on the Immune Function Through Its Antioxidation and Anti-Apoptosis in D-Galactose-Induced Aging Mice.

BACKGROUND: Aging is a spontaneous and inevitable phenomenon of biology, which can lead to the gradual deterioration of tissues and organs. One of the age-related deterioration processes is immunosenescence, which leads to changes in the function of immune systems, including immune cells and associated cytokines. A proper modulation of immune responses can improve the age-related immunosenescence process and then reach healthy aging. Schisandra sphenanthera, a traditional Chinese medicine, has been used as both a medicine and a nutritional supplement for thousands of years. Anwulignan, a monomer compound of Schisandra sphenanthera lignans, has been reported to possess an immunomodulatory effect. Therefore, this study was designed to further explore whether Anwulignan could also modulate the immune functions in aging model mice and the underlying mechanism. METHODS: D-galactose (D-gal) is often used as an inducer of immunosenescence in animals. In this study, a mice model was created by subcutaneous D-gal (220 mg kg-1) for successive 42 days. Then, the blood and spleen tissue samples were taken for the analysis and observation of cytokine levels, immunoglobulin levels, leukocyte numbers, and the phagocytic activity of macrophages, as well as the histological changes, the proliferation ability of lymphocytes, and the biochemical parameters in the spleen tissue. RESULTS: Anwulignan significantly increased the serum levels of IL-2, IL-4, IFN-γ, lgG, lgM, and lgA, decreased the content of TNF-α and IL-6 in the aging mice, and increased the blood leukocyte number, the phagocytic activity, the lymphocyte proliferation, and the spleen index in vitro. Anwulignan also significantly increased the activities of SOD and GSH-Px, decreased the contents of MDA and 8-OHdG in the spleen tissue, up-regulated the expressions of Nrf2, HO-1, and Bcl2, down-regulated the expressions of Keap1, Caspase-3, and Bax in the spleen cells, and reduced the apoptosis of spleen lymphocytes. CONCLUSION: Anwulignan can restore the immune function that is declined in D-gal-induced aging mice partly related to its antioxidant capacity by activating the Nrf2/ARE pathway and downstream enzymes, as well as its anti-apoptotic effect by regulating Caspase-3 and the ratio of Bcl2 to Bax in the spleen.

Diet supplemented with phytochemical epigallocatechin gallate and probiotic Lactobacillus fermentum confers second generation synbiotic effects by modulating cellular immune responses and antioxidant capacity in aging mice.

PURPOSE: In the present study, we systematically identified and evaluated a synbiotic combination of phytochemical epigallocatechin gallate (EGCG) and probiotic bacteria in amelioration of immunosenescence and oxidative stress in aged mice. METHODS: Inhibitory effects of EGCG against different bacterial species were evaluated in vitro, followed by analysis to identify potential combination of EGCG and probiotic bacteria against alleviation of oxidative and inflammatory stress ex vivo. The best synbiotic combination, vis-à-vis prebiotic and probiotic supplementation alone, was then evaluated in aged Swiss albino mice for modulation of various immunological and antioxidative parameters. RESULTS: EGCG strongly inhibited the growth of pathogenic microbes as compared to probiotic bacteria. A combination of EGCG with probiotic Lactobacillus fermentum (LF) provided evidence of additive effects in the amelioration of oxidative and inflammatory stress-induced cell death. In vivo study revealed that combined supplementation of LF and EGCG significantly enhanced neutrophil oxidative index, CD3+ cell numbers and activation status, Th1/Th2 cytokines in splenic supernatants as well as liver Nrf-2 expression in comparison with treatments with LF or EGCG alone. The combined application of EGCG and LF did not simply result in additive or synergistic effects in relation with individual treatments. CONCLUSION: These observations suggest that EGCG could be considered as a potential prebiotic that can offer second generation synbiotic health beneficial effects for the alleviation of some of the deleterious aspects of immunosenescence and aging.

Voluntary exercise reverses immune aging induced by oxidative stress in aging mice.

Excessive oxidative stress leads to aging due to persistent damage to the cells, tissues, and the entire organism. Immunosenescence is also a devastating consequence of oxidative stress, but there is a lack of research on effective ways to overcome it. In this study, we used physiologic and immunological aging mouse models that had sustained oxidative stress to investigate whether voluntary exercise and/or antioxidant treatment could overcome oxidative damage as well as aging. We established an aging model induced by continuously administering d-galactose (d-gal) to 6-week-old female C57BL/6J mice. We also assessed reversal of immunosenescence by providing free-wheel running and vitamin E (vit E) supplementation to this aging model. As an aging index, the level of advanced glycation end products (AGEs) in the blood was measured. Phenotypes of T cells in the thymus and spleen were examined as an index of immunosenescence. Intracellular reactive oxygen species (ROS) levels in the mouse spleen and levels of AGEs in the blood were significantly higher after 6 weeks of d-gal administration. In addition, immunosenescence was observed, in which the naïve:effector cell ratio in the spleen decreased. After 4 weeks of free-wheel running and vit E administration, both intracellular ROS and serum AGE levels decreased. Above all, free-wheel running restored the naïve:effector ratio of cytotoxic T lymphocytes reduced by d-gal administration. Taken together, these results suggest that voluntary exercise may be effective in restoring immunosenescence induced by oxidative stress.

Immunosenescence-like state is accelerated by constant light exposure and counteracted by melatonin or turmeric administration through DJ-1/Nrf2 and P53/Bax pathways.

The awareness of the interrelationship between immunosenescence and constant light exposure can provide new insights into the consequences of excessive exposure to light at night due to light pollution or shift work. Here, we investigated whether constant light exposure (LL) acts as an inducer of immunosenescence. We also determined the role of melatonin or turmeric in reversing the putative effects of constant light and explored for the first time the underlying molecular mechanisms. Young (3-4-month-old) rats were exposed daily to LL alone or in combination with each of melatonin and turmeric for 12 weeks. A group of aged rats (18-months old; n = 6) was used as a reference for natural immunosenescence. Constant light exposure resulted in remarkable pathophysiological alterations resembling those noticed in normal aged rats, manifested as apparent decreases in antioxidant activities as well as Nrf2 and DJ-1 expressions, striking augmentation in oxidative stress, proinflammatory cytokines and expression of TNFα, Bax, and p53 genes, and deleterious changes of lymphoid organs, Co-administration of melatonin or turmeric was able to reverse all alterations induced by LL through upregulation of Nrf2/DJ-1 and downregulation of p53/Bax pathways. These data suggest that LL accelerates immunosenescence via oxidative stress and apoptotic pathways. They also demonstrate for the first time that turmeric is comparable to melatonin in boosting the immune function and counteracting the LL-associated immunosenescence. These effects suggest that turmeric supplementation can be used as an inexpensive intervention to prevent circadian disruption-related immunosenescence. However, to validate the effects of turmeric on humans further studies are warranted.

Effects of Fish Oil on HIV-Related Inflammation and Markers of Immunosenescence: A Randomized Clinical Trial.

OBJECTIVE: To explore the safety and efficacy of fish oil to modulate parameters of inflammation and immunosenescence in HIV-infected older adults. DESIGN: This study uses a randomized, controlled, double-blind clinical trial. SETTING: The study was conducted in an outpatient HIV/AIDS clinic in a large urban Midwestern city in the United States. SUBJECTS: A total of 37 clinically stable HIV-infected adults between the ages of 40 and 70 years of age participated. INTERVENTIONS: Fish oil 1.6 g/day was administered for 12 weeks or placebo. OUTCOME MEASURES: Inflammatory cytokine production, surface markers of immunosenescence, and adverse events were measured. RESULTS: After 12 weeks of supplementation, there were no significant differences between the treatment and control groups on any measures of inflammation or immunosenescence in both CD4+ and CD8+ T lymphocytes. More participants in the treatment group reported adverse gastrointestinal events compared with the control group. CONCLUSIONS: A 12-week supplementation regimen of 1.6 g/day of fish oil did not favorably modulate parameters of inflammation or immune senescence in HIV-infected adults. Future studies should test agents that directly target mechanisms that underlie HIV-related inflammation to determine whether reducing inflammation can reverse immunosenescence.

Dietary Animal Plasma Proteins Improve the Intestinal Immune Response in Senescent Mice.

Increased life expectancy has promoted research on healthy aging. Aging is accompanied by increased non-specific immune activation (inflammaging) which favors the appearance of several disorders. Here, we study whether dietary supplementation with spray-dried animal plasma (SDP), which has been shown to reduce the activation of gut-associated lymphoid tissue (GALT) in rodents challenged by S. aureus enterotoxin B (SEB), and can also prevent the effects of aging on immune system homeostasis. We first characterized GALT in a mouse model of accelerated senescence (SAMP8) at different ages (compared to mice resistant to accelerated senescence; SAMR1). Second, we analyzed the SDP effects on GALT response to an SEB challenge in SAMP8 mice. In GALT characterization, aging increased the cell number and the percentage of activated Th lymphocytes in mesenteric lymph nodes and Peyer's patches (all, p < 0.05), as well as the expression of IL-6 and TNF-α in intestinal mucosa (both, p < 0.05). With respect to GALT response to the SEB challenge, young mice showed increased expression of intestinal IL-6 and TNF-α, as well as lymphocyte recruitment and activation (all, p < 0.05). However, the immune response of senescent mice to the SEB challenge was weak, since SEB did not change cell recruitment or the percentage of activated Th lymphocytes. Mice supplemented with SDP showed improved capacity to respond to the SEB challenge, similar to the response of the young mice. These results indicate that senescent mice have an impaired mucosal immune response characterized by unspecific GALT activation and a weak specific immune response. SDP supplementation reduces non-specific basal immune activation, allowing for the generation of specific responses.

Oxidative stress and immunosenescence in spleen of obese mice can be reversed by 2-hydroxyoleic acid.

NEW FINDINGS: What is the central question of this study? Evidence is growing for the link between obesity, immune dysfunction and oxidative stress, but it is still not known how the properties and functions of the spleen and splenic leucocytes are affected. What is the main finding and its importance? Obesity led to premature immunosenescence, manifested as oxidative stress and changes in leucocyte functions in mouse spleen. The oleic acid derivative 2-hydroxyoleate and, to a lesser extent, a combination of eicosapentaenoic and docosahexaenoic acids could reverse most of the observed alterations, suggesting a potential therapeutic tool for obesity-related immune dysfunction and redox imbalance. We aimed to investigate the effects of obesity on oxidative stress and leucocyte function in the mouse spleen and to assess whether supplementation with 2-hydroxyoleic acid (2-OHOA) or n-3 polyunsaturated fatty acids (PUFAs) could reverse those effects. Female ICR/CD1 mice (8 weeks old, n = 24) received an obesogenic diet (22% fat for 4 weeks and 60% fat for 14 weeks). After 6 weeks, mice were divided into the following three groups (n = 8 per group): no supplementation; 2-OHOA supplementation (1500 mg kg-1 of diet); and n-3 PUFA supplementation (eicosapentaenoic acid and docosahexaenoic acid, 1500 + 1500 mg kg-1 of diet). Eight mice were fed the standard diet for the whole duration of the study (control group). At the end of the experiment, the following variables were assessed in spleens: levels of reduced (GSH) and oxidized glutathione (GSSG), GSH/GSSG, xanthine oxidase activity, lipid peroxidation, lymphocyte chemotaxis, natural killer activity and mitogen (concanavalin A and lipopolysaccharide)-induced lymphocyte proliferation. Obese animals presented higher GSSG levels (P = 0.003), GSSG/GSH ratio (P = 0.013), lipid peroxidation (P = 0.004), xanthine oxidase activity (P = 0.015) and lymphocyte chemotaxis (P < 0.001), and lower natural killer activity (P = 0.003) and proliferation in response to concanavalin A (P < 0.001) than control mice. 2-Hydroxyoleic acid totally or partly reversed most of the changes (body weight, fat content, GSSG levels, GSH/GSSG, lipid peroxidation, chemotaxis and proliferation, all P < 0.05), whereas n-3 PUFAs reversed the increase in xanthine oxidase activity (P = 0.032). In conclusion, 2-OHOA or, to a lesser extent, n-3 PUFAs could ameliorate the oxidative stress and alteration of leucocyte function in the spleens of obese mice. Our findings support a link between obesity and immunosenescence and suggest a potential therapeutic tool for obesity-related immune dysfunction.

[Effects of serums containing Buzhong Yiqi decoction with Astragalus Radix or Hedysari Radix on anti-immunosenescence in spleen lymphocytes of SAMP8 mice].

This paper was aimed to compare the effect of Buzhong Yiqi decoction containing Hedysari Radix or Astragali Radix on anti-immunosenescence effects in spleen lymphocytes of senescence accelerated mouse 8 (SAMP8). The effect of the serums on the proliferation of spleen T lymphocytes in SAMP8 mice induced by ConA was tested by MTT. The effect of the serums on the T lymphocytes subsets of SAMP8 mice was measured by flow cytometry. ELISA was used to detect the level of IL-2 and IFN-γ in the culture supernatants of spleen lymphocytes. The effect of the serums on the expression of CD28 mRNA in spleen T lymphocytes was detected by fluorescent quantitative PCR. Western blot was used to detect the expression of CD28 protein in spleen T lymphocytes of SAMP8 mice. Both the serums of Buzhong Yiqi decoctions containing Hedysari Radix or Astragali Radix improved the proliferation of T lymphocytes in SAMP8 mice. Both the serums had no obvious effect on the differentiation of spleen T lymphocytes'subsets in SAMP8 mice. Both the serums increased the content of IL-2 and INF-γ in the culture supernatants of spleen lymphocytes. And for the content of IL-2, the serum of Buzhong Yiqi decoction with Hedysari Radix was better（P<0.05）. Both the serums improved the expression of CD28 mRNA in spleen T lymphocytes of SAMP8 mice. And the effect of Hedysari Radix group was better than that of Astragalus Radix group（P<0.05）. Both the serums improved the expression of CD28 protein in spleen T lymphocytes of SAMP8 mice. The role of the serums containing Buzhong Yiqi decoction with Astragalus Radix and the decoction with Hedysari Radix in anti-immunosenescence was through the effect of the CD28. And the effect of Hedysari Radix group was better than that of Astragalus Radix group on improved the expression of CD28 mRNA in T lymphocytes of SAMP8 mice. Astragalus Radix and Hedysari Radix could swap in the aspect of anti-immunosenescence.