Two experiments were conducted to determine the conjugated linoleic acid (CLA) content of milk from cows offered diets rich in linoleic and linolenic acid. In experiment 1, 36 cows were assigned to a control and five treatment groups. Cows in the control group received a diet containing 51% forage and 49% grain on a dry matter basis. In the treatment group, grain was partly replaced by either 18% raw cracked soybeans, 18% roasted cracked soybeans, 3.6% soybean oil, 2.2% linseed oil, or 4.4% linseed oil. Experimental diets were fed for 5 wk. Average CLA contents in milk fat from wk 2 through 5 were 0.39% in control and 0.37, 0.77, 2.10, 1.58, and 1.63% of total fatty acids in the raw soybean, roasted soybeans, soybean oil, 2.2% linseed oil, and 4.4% linseed oil treatments, respectively. In experiment 2, 36 cows were assigned to a control and 5 treatment groups. Cows in the control group received a diet containing 55% forage and 45% grain. In the treatment groups, grain was partly replaced by soybean oil at 0.5, 1.0, 2.0, 4.0, or by linseed oil at 1.0% of the dietary dry matter. Experimental diets were fed for 5 wk. Average CLA contents in milk fat from wk 2 through 5 were 0.50% in control and 0.75, 0.76, 1.45, 2.08, and 0.73% of total fatty acids in 0.5, 1.0, 2.0, 4.0 soybean oil and 1.0% linseed oil treatments, respectively. Diets rich in linoleic or linolenic acid can increase CLA content of milk when dietary oil is accessible to the rumen microorganisms.

Hydrogen peroxide (H2O2) is an essential second intracellular messenger. To reach its targets in the cytosol, H2O2 must cross a membrane, a feat that requires aquaporins (AQP) endowed with ‘peroxiporin’ activity (AQP3, AQP8, AQP9). Here, we exploit different organelle-targeted H2O2-sensitive probes to show that also AQP11 efficiently conduits H2O2. Unlike other peroxiporins, AQP11 is localized in the endoplasmic reticulum (ER), accumulating partly in mitochondrial-associated ER membranes (MAM). Its downregulation severely perturbs the flux of H2O2 through the ER, but not through the mitochondrial or plasma membranes. These properties make AQP11 a potential regulator of ER redox homeostasis and signaling.

HO acts as a second messenger in key signaling circuits, transiently modulating tyrosine phosphatases and kinases. We investigated its origin, membrane transport, and functional role during B cell activation and differentiation. Our data identified NADPH-oxidase 2 as the main source of HO and aquaporin 8 as a transport facilitator across the plasma membrane. On aquaporin 8 silencing, inducible B lymphoma cells responded poorly to TLR and BCR stimulation. Their differentiation was severely impaired, as demonstrated by retarded onset of IgM polymerization, low amounts of IgM secretion, and prolonged BCR expression on the cell surface. A silencing-resistant aquaporin 8 rescued responsiveness, confirming that the import of HO across the membrane is essential for B cell activation. The addition of exogenous catalase to primary B splenocytes severely impaired the tyrosine phosphorylation induced by BCR cross-linking, as did the absence of NOX2 in a murine model of chronic granulomatous disease. Importantly, re-expression of gp91 through gene therapy restored the specific B cell signaling deficiency in NOX2 cells. Thus, efficient induction of B cell activation and differentiation requires intact HO fluxes across the plasma membrane for signal amplification.

A two-step posttranslational modification of AQP8 provides a mechanism regulating plasma membrane H2O2 conductance.

Berries are considered “promising functional fruits” due to their distinct and ubiquitous therapeutic contents of anthocyanins, proanthocyanidins, phenolic acids, flavonoids, flavanols, alkaloids, polysaccharides, hydroxycinnamic, ellagic acid derivatives, and organic acids. These polyphenols are part of berries and the human diet, and evidence suggests that their intake is associated with a reduced risk or the reversal of metabolic pathophysiologies related to diabetes, obesity, oxidative stress, inflammation, and hypertension. This work reviewed and summarized both clinical and non-clinical findings that the consumption of berries, berry extracts, purified compounds, juices, jams, jellies, and other berry byproducts aided in the prevention and or otherwise management of type 2 diabetes mellitus (T2DM) and related complications. The integration of berries and berries-derived byproducts into high-carbohydrate (HCD) and high-fat (HFD) diets, also reversed/reduced the HCD/HFD-induced alterations in glucose metabolism-related pathways, and markers of oxidative stress, inflammation, and lipid oxidation in healthy/obese/diabetic subjects. The berry polyphenols also modulate the intestinal microflora ecology by opposing the diabetic and obesity rendered symbolic reduction of Bacteroidetes/Firmicutes ratio, intestinal mucosal barrier dysfunction-restoring bacteria, short-chain fatty acids, and organic acid producing microflora. All studies proposed a number of potential mechanisms of action of respective berry bioactive compounds, although further mechanistic and molecular studies are warranted. The metabolic profiling of each berry is also included to provide up-to-date information regarding the potential anti-oxidative/antidiabetic constituents of each berry.

Adipose tissue (AT) is an endocrine organ involved in the management of energy metabolism via secretion of adipokines, hormones, and recently described secretory microvesicles, i.e., exosomes. Exosomes are rich in possible biologically active factors such as proteins, lipids, and RNA. The secretory function of adipose tissue is affected by pathological processes. One of the most important of these is obesity, which triggers adipose tissue inflammation and adversely affects the release of beneficial adipokines. Both processes may lead to further AT dysfunction, contributing to changes in whole-body metabolism and, subsequently, to insulin resistance. According to recent data, changes within the production, release, and content of exosomes produced by AT may be essential to understand the role of adipose tissue in the development of metabolic disorders. In this review, we summarize actual knowledge about the possible role of AT-derived exosomes in the development of insulin resistance, highlighting methodological challenges and potential gains resulting from exosome studies.

Aquaporins (AQPs) are part of the family of the integral membrane proteins. Their function is dedicated to the transport of water, glycerol, ammonia, urea, H 2 O 2 , and other small molecules across the biological membranes. Although for many years they were scarcely considered, AQPs have a relevant role in the development of many diseases. Recent discoveries suggest, that AQPs may play an important role in the process of fat accumulation and regulation of oxidative stress, two crucial aspects of insulin resistance and type-2 diabetes (T2D). Insulin resistance (IR) and T2D are multi-faceted systemic diseases with multiple connections to obesity and other comorbidities such as hypertension, dyslipidemia and metabolic syndrome. Both IR and T2D transcends different tissues and organs, creating the maze of mutual relationships between adipose fat depots, skeletal muscle, liver and other insulin-sensitive organs. AQPs with their heterogenous properties, distinctive tissue distribution and documented involvement in both the lipid metabolism and regulation of the oxidative stress appear to be feasible candidates in the search for the explanation to this third-millennium plague. A lot of research has been assigned to adipose tissue AQP7 and liver tissue AQP9, clarifying their relationship and coordinated work in the induction of hepatic insulin resistance. Novel research points also to other aquaporins, such as AQP11 which may be associated with the induction of insulin resistance and T2D through its involvement in hydrogen peroxide transport. In this review we collected recent discoveries in the field of AQP's involvement in the insulin resistance and T2D. Novel paths which connect AQPs with metabolic disorders can give new fuel to the research on obesity, insulin resistance and T2D - one of the most worrying problems of the modern society.

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