In vivo and ex vivo studies support the immunostimulant and immunoprotective effect of Damiana (Turnera diffusa Willd) in Almaco Jack (Seriola rivoliana).

Damiana (Turnera diffusa Willd) was evaluated in vitro for antioxidant and antibacterial activities against Staphylococcus aureus and Streptococcus pyogenes (as a preliminary screening assessment) by high-performance thin-layer chromatography (HPTLC)-Direct bioautography. A study was performed in vivo to evaluate the effects of Damiana enriched diets at 0.5 % on immune parameters in mucus and serum and gene expression in Almaco Jack (Seriola rivoliana) intestine after two and four weeks; an infection with Aeromonas hydrophila at 1x107 colony forming units (CFU) followed and an ex vivo study was carried out using head-kidney leukocytes. Ferric reducing ability of plasma (FRAP) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays showed high antioxidant activities in Damiana leaves; even in the ABTS assay, Damiana at 300 µg/mL showed similar activity to ascorbic acid - the standard control. Damiana exhibited strong in vitro antimicrobial activity against S. aureus and S. pyogenes. In vivo studies showed a strong enhancement of myeloperoxidase, nitric oxide, superoxide dismutase, and catalase activities in mucus and serum of S. rivoliana supplemented with Damiana; their immunological response enhanced after infection with A. hydrophila. IL-1ß, TNF-α, and IL-10 gene expressions upregulated in the fish intestine challenged with the bacterium. Piscidin and macrophage (MARCO) receptor gene expression up-regulated at week 4 and down-regulated after infection. Intestinal histology results confirm that Damiana not cause inflammation or damage. Finally, the ex vivo study confirmed the immunostimulant and protective effects of Damiana through increased phagocytic, respiratory burst, myeloperoxidase activities and nitric oxide generation before and upon the bacterial encounter. These results support the idea that Damiana has the potential as an immunostimulant additive for diets in aquaculture by enhancing immune parameters and protecting Almaco Jack against A. hydrophila infections upon four weeks of supplementation.

Associations between Dietary Fatty Acid Profile and Milk Fat Production and Fatty Acid Composition in Dairy Cows: A Meta-Analysis.

This meta-analysis aimed to investigate the effect of dietary fatty acid (FA) profile on milk fat production and FA profile in dairy cows. The study also aimed to develop prediction models using a meta-regression approach. The database included 217 peer-reviewed articles on lactating dairy cows (n = 12,892), consisting of 515 treatment means. Effect size was assessed using the raw mean differences between diets with supplementary lipid sources and those without. Subgroup analyses were employed to assess heterogeneity. Diets rich in saturated FA (SFA) increased milk fat production and proportion, while reducing de novo FA in milk. Diets high in monounsaturated FA and polyunsaturated FA decreased mixed FA in milk. Most lipid-supplemented diets increase preformed FA in milk, except those rich in SFA. Prediction models were developed using meta-regression. Key predictors of milk fat production included neutral detergent fiber (NDF), dietary myristic acid, and milk production. Milk fat proportion was best predicted by dietary unsaturated FA, NDF, and forage. De novo FA in milk was predicted by dry matter intake (DMI) and dietary FA, while preformed FA was predicted by DMI, dietary oleic and linoleic acids. In conclusion, this study emphasizes the importance of the dietary FA profile in evaluating the effects of lipids on milk fat production and FA profile. Accurate and precise predictions of milk fat production, proportion, and FA profile can be achieved by considering cow production and dietary characteristics.

Successful pregnancy in a CKD patient on a low-protein, supplemented diet: an opportunity to reflect on CKD and pregnancy in Mexico, an emerging country.

Pregnancy is probably the most important challenge in young women with chronic kidney disease (CKD). The challenge is greater in developing countries, in which access to dialysis is uneven, and prenatal care for CKD patients is not uniformly available. This case report summarizes some of the challenges faced by pregnant CKD women in a developing country. A 35-year-old woman, affected by an undiagnosed kidney disease, experienced preeclampsia at 24 years of age, and started dialysis in emergency at age 31 in the context of severe preeclampsia in her second pregnancy. Following slow recovery of kidney function, after 18 months of dialysis she started a moderately restricted, supplemented, low-protein diet, which allowed her to discontinue dialysis. A few months after dialysis discontinuation, she started a new pregnancy in the presence of severely reduced kidney function (serum creatinine 4.6 mg/dl at the last pre-pregnancy control). Interestingly, she discontinued nephrology and nutritional follow-up, mainly because she was worried that she would be discouraged from continuing the pregnancy, but also because she continued to feel well. She self-managed her diet in pregnancy and delivered a healthy baby, with normal intrauterine growth, at term; while the last laboratory data confirmed the presence of severe kidney function impairment, she is still dialysis-free at the time of the present report. Her story, with its happy ending, underlines the importance of dedicated programs for CKD pregnancies in developing countries and confirms the safety of moderately protein-restricted diets in pregnancy.

ß-1,3/1,6-Glucan-supplemented diets antagonize immune inhibitory effects of hypoxia and enhance the immune response to a model vaccine.

The diets of farmed salmon are usually supplemented with immunostimulants to improve health status. Because ß-glucan is one of the most common immunostimulants used in diets, here we examined the effect of two ß-1,3/1,6-glucan-supplemented diets on the expression of immune response genes of Atlantic salmon. The relative abundances of IFN-α1, Mx, IFN-γ, IL-12, TGF-ß1, IL-10, and CD4 transcripts were evaluated in head kidney by qRT-PCR. We assessed the effects of the diets under normoxia and acute hypoxia, as salmon are especially sensitive to changes in the concentration of dissolved oxygen, which can also affect immunity. These effects were also tested on vaccinated fish, as we expected that ß-1,3/1,6-glucan-supplemented diets would enhance the adaptive immune response to the vaccine. We found that administration of the Bg diet (containing ß-1,3/1,6-glucan) under normoxia had no effects on the expression of the analyzed genes in the kidney of the diet-fed fish, but under hypoxia/re-oxygenation (90 min of acute hypoxia), the ßg diet affected the expression of the antiviral genes, IFN-α1 and Mx, preventing their decrease caused by hypoxia. The Bax diet, which in addition to ß-1,3/1,6-glucan, contained astaxanthin, increased IL-12 and IFN-γ in kidneys. With fish exposed to hypoxia/reoxygenation, the diet prevented the decrease of IFN-α1 and Mx levels observed after hypoxia. When fish were vaccinated, only the levels of IL-12 and CD4 transcripts increased, but interestingly if fish were also fed the Bax diet, the vaccination induced a significant increase in all the analyzed transcripts. Finally, when vaccinated fish were exposed to hypoxia, the effect of the Bax diet was greatly reduced for all genes tested and moreover, inducible effects completely disappeared for IL-12, IFN-α, and Mx. Altogether, these results showed that the tested ß-1,3/1,6-glucan diets increased the levels of transcripts of key genes involved in innate and adaptive immune response of salmon, potentiating the response to a model vaccine and also antagonizing the effects of hypoxia.