L-Glutamine Supplementation Enhances Strength and Power of Knee Muscles and Improves Glycemia Control and Plasma Redox Balance in Exercising Elderly Women.

We investigated the effects of oral L-glutamine (Gln) supplementation, associated or not with physical exercises, in control of glycemia, oxidative stress, and strength/power of knee muscles in elderly women. Physically active (n = 21) and sedentary (n = 23) elderly women aged 60 to 80 years were enrolled in the study. Plasma levels of D-fructosamine, insulin, reduced (GSH) and oxidized (GSSG) glutathione, iron, uric acid, and thiobarbituric acid-reactive substances (TBARs) (lipoperoxidation product), as well as knee extensor/flexor muscle torque peak and average power (isokinetic test), were assessed pre- and post-supplementation with Gln or placebo (30 days). Higher plasma D-fructosamine, insulin, and iron levels, and lower strength/power of knee muscles were found pre-supplementation in the NPE group than in the PE group. Post-supplementation, Gln subgroups showed higher levels of GSH, GSSG, and torque peak, besides lower D-fructosamine than pre-supplementation values. Higher muscle average power and plasma uric acid levels were reported in the PE + Gln group, whereas lower insulin levels were found in the NPE + Gln than pre-supplementation values. TBARs levels were diminished post-supplementation in all groups. Gln supplementation, mainly when associated with physical exercises, improves strength and power of knee muscles and glycemia control, besides boosting plasma antioxidant capacity of elderly women.

Elderly Subjects Supplemented with L-Glutamine Shows an Improvement of Mucosal Immunity in the Upper Airways in Response to Influenza Virus Vaccination.

BACKGROUND: Although glutamine is able to improve the immune response, its action in the upper airway immunity against the influenza virus vaccine remains unclear. Therefore, we aimed to evaluate the L-glutamine supplementation effect on the mucosal immune/inflammatory response of elderly subjects vaccinated against the influenza virus. METHODS: Saliva sampling from 83 physically active elderly volunteers were collected pre- and 30 days after influenza virus vaccination and supplementation with L-glutamine (Gln, n = 42) or placebo (PL, n = 41). RESULTS: Gln group showed higher salivary levels of interleukin (IL)-17, total secretory immunoglobulin A (SIgA), and specific-SIgA post-vaccination than values found pre-vaccination and in the PL group post-vaccination. Whereas higher salivary levels of IL-6 and IL-10 were observed post-vaccination in the Gln group, IL-37 levels were lower post-vaccination in both groups than the values pre-vaccination. Tumor necrosis factor (TNF)-α levels were unchanged. Positive correlations between IL-6 and IL-10 were found in all volunteer groups pre- and post-vaccination and also between IL-17 and IL-6 or IL-10 in the Gln group post-vaccination. A negative correlation between IL-37 and IL-10 was found pre- and post-vaccination in the PL group. CONCLUSION: Gln supplementation was able to modulate salivary cytokine profile and increase SIgA levels, both total and specific to the influenza virus vaccine, in physically active elderly subjects.

Combined Exercise Training and l-Glutamine Supplementation Enhances Both Humoral and Cellular Immune Responses after Influenza Virus Vaccination in Elderly Subjects.

BACKGROUND: Since aging affects the immune responses against vaccination, the present study evaluated the effects of L-glutamine (Gln) supplementation in the humoral and cellular immune responses in elderly subjects, practitioners or not, of physical exercise training. METHODS: Eighty-four elderly people (aged 72.6 ± 6.1), non-practitioners (NP, n = 31), and practitioners of combined-exercise training (CET, n = 53) were submitted to Influenza virus vaccination and supplemented with Gln (0.3 g/kg of weight + 10 g of maltodextrin, groups: NP-Gln (n = 14), and CET-Gln (n = 26)), or placebo (10 g of maltodextrin, groups: NP-PL (n = 17), and CET-PL (n = 27)). Blood samples were collected pre (baseline) and 30 days post-vaccination and supplementation. RESULTS: Comparing with the baseline values, whereas the NP-Gln and CET-PL groups showed higher specific-IgM levels, the CET-Gln group showed higher specific-IgM and IgA levels post-vaccination. The titer rate of hemagglutination inhibition was higher in the CET-Gln, NP-PL, and NP-Gln groups post-vaccination than baseline values. The absolute number of naive and effector CD4+ T cells was higher especially in the NP-Gln and CET-Gln groups, whilst activated CD4+ T cells were higher in CET subgroups post-vaccination. CONCLUSION: Our results showed that both l-glutamine supplementation and combined-exercise training can improve the immune responses to the Influenza virus vaccine in elderly subjects.

L-Glutamine Supplementation Improves the Benefits of Combined-Exercise Training on Oral Redox Balance and Inflammatory Status in Elderly Individuals.

Although regular combined aerobic-resistance exercises can ameliorate the inflammatory status and redox balance in elderly population, it is unclear whether protein or specific amino acid supplementation could improve such benefits. Therefore, we aimed to evaluate the inflammatory status and redox indexes through of the saliva of 34 elderly subject nonpractitioners (NP group, 73.3 ± 6.6 years) and 49 elderly subject practitioners of a combined-exercise training in moderate intensity (CET group, 71.9 ± 5.8 years) before (pre) and after (post) 30 days of supplementation with L-glutamine (Gln) or placebo (PL). Our results showed that, both in pre- and postsupplementation, the salivary levels of nitric oxide (NO·) and TNF-α were lower, whereas the levels of uric acid and IL-10 (as well as IL-10/TNF-α ratio) were higher in the CET groups than in the NP groups. In postsupplementation, both groups supplemented with Gln (NP-Gln and CET-Gln) showed higher salivary uric acid levels compared to baseline. In addition, lower NO· levels were found in the CET-Gln group postsupplementation than presupplementation values. Whereas the CET-Gln group showed lower GSH levels postsupplementation, NP-Gln subjects showed lower GSSG levels at the same time point, both compared to baseline. Interestingly, salivary peroxidase activity was lower only in NP groups (NP-PL and NP-Gln) postsupplementation than baseline values. A positive significant correlation between salivary peroxidase activity and GSH levels, and also between salivary peroxidase activity and uric acid levels were observed in the CET-Gln group both pre- and postsupplementation. No differences were found in albumin, total antioxidant activity (TEAC), and reducing power analysis between groups, pre- or postsupplementation. In conclusion, the elderly subjects from the CET group showed a better inflammatory response and redox balance and, for the first time, it was shown that daily supplementation with Gln for 30 days can improve these benefits with putative association with a healthy aging.

A Mixture of Polyunsaturated Fatty Acids ω-3 and ω-6 Reduces Melanoma Growth by Inhibiting Inflammatory Mediators in the Murine Tumor Microenvironment.

BACKGROUND: Although it has been previously demonstrated that acute inflammation can promote the tumor growth of a sub-tumorigenic dose of melanoma cells through of 5-lipoxygenase inflammatory pathway and its product leukotriene B4, and also that the peritumoral treatment with eicosapentaenoic acid and its product, leukotriene B5, reduces the tumor development, the effect of the treatment by gavage with omega-3 and omega-6 in the tumor microenvironment favorable to melanoma growth associated with acute inflammation has never been studied. METHODS: C57BL/6 mice were coinjected with 1 × 106 apoptotic cells plus 1 × 103 viable melanoma cells into the subcutaneous tissue and treated by gavage with omega-3-rich fish oil or omega-6-rich soybean oil or a mixture of these oils (1:1 ratio) during five consecutive days. RESULTS: The treatment by gavage with a mixture of fish and soybean oils (1:1 ratio) both reduced the melanoma growth and the levels of leukotriene B4 (LTB4), prostaglandin E2 (PGE2), PGE2/prostaglandin E3 (PGE3) ratio, and CXC ligand 1 (CXCL1) and increased the levels of interleukin 10 (IL-10) to IL-10/CXCL1 ratio in the melanoma microenvironment. CONCLUSION: The oral administration of a 1:1 mixture of fish oil and soybean oil was able to alter the release of inflammatory mediators that are essential for a microenvironment favorable to the melanoma growth in mice, whereas fish oil or soybean oil alone was ineffective.