L-Arginine Modulates Intestinal Inflammation in Rats Submitted to Mesenteric Ischemia-Reperfusion Injury.

BACKGROUND: The goal of this study was to investigate whether exogenous offer of L-arginine (LARG) modulates the gene expression of intestinal dysfunction caused by ischemia and reperfusion. METHODS: Eighteen Wistar-EPM1 male rats (250-300 g) were anesthetized and subjected to laparotomy. The superior mesenteric vessels were exposed, and the rats were randomized into 3 groups (n = 6): the control group (CG), with no superior mesenteric artery interruption; the ischemia/reperfusion group (IRG), with 60 minutes of ischemia and 120 minutes of reperfusion and saline injections; and the L-arginine group (IRG + LARG), with L-arginine injected in the femoral vein 5 minutes before ischemia, 5 minutes after reperfusion, and after 55 minutes of reperfusion. The total RNA was extracted and purified from samples of the small intestine. The concentration of each total RNA sample was determined by using spectrophotometry. The first-strand complementary DNA (cDNA) was synthesized in equal amounts of cDNA and the Master Mix SYBR Green qPCR Mastermix (SABiosciences, a Qiagen Company, Frederick, Md). Amounts of cDNA and Master Mix SYBR Green qPCR Mastermix were distributed to each well of the polymerase chain reaction microarray plate containing the predispensed gene-specific primer sets for Bax and Bcl2. Each sample was evaluated in triplicate, and the Student t test was applied to validate the homogeneity of each gene expression reaction (P < .05). RESULTS: The gene expression of Bax in IRG (+1.48) was significantly higher than in IRG-LARG (+9.69); the expression of Bcl2L1 in IRG (+1.01) was significantly higher than IRG-LARG (+22.89). CONCLUSIONS: The apoptotic cell pathway of 2 protagonists showed that LARG improves the gene expression of anti-apoptotic Bcl2l1 (Bcl2-like 1) more than the pro-apoptotic Bax (Bcl2-associated X protein).

Effects of adding polyclonal antibody preparations on ruminal fermentation patterns and digestibility of cows fed different energy sources.

Nine ruminally cannulated cows fed different energy sources were used to evaluate an avian-derived polyclonal antibody preparation (PAP-MV) against the specific ruminal bacteria Streptococcus bovis, Fusobacterium necrophorum, Clostridium aminophilum, Peptostreptococcus anaerobius, and Clostridium sticklandii and monensin (MON) on ruminal fermentation patterns and in vivo digestibility. The experimental design was three 3 × 3 Latin squares distinguished by the main energy source in the diet [dry-ground corn grain (CG), high-moisture corn silage (HMCS), or citrus pulp (CiPu)]. Inside each Latin square, animals received one of the feed additives per period [none (CON), MON, or PAP-MV]. Dry matter intake and ruminal fermentation variables such as pH, total short-chain fatty acids (tSCFA), which included acetate, propionate, and butyrate, as well as lactic acid and NH(3)-N concentration were analyzed in this trial. Total tract DM apparent digestibility and its fractions were estimated using chromic oxide as an external marker. Each experimental period lasted 21 d. Ruminal fluid sampling was carried out on the last day of the period at 0, 2, 4, 6, 8, 10, and 12 h after the morning meal. Ruminal pH was higher (P = 0.006) 4 h postfeeding in MON and PAP-MV groups when compared with CON. Acetate:propionate ratio was greater in PAP-MV compared with MON across sampling times. Polyclonal antibodies did not alter (P > 0.05) tSCFA, molar proportion of acetate and butyrate, or lactic acid and NH(3)-N concentration. Ruminal pH was higher (P = 0.01), 4 h postfeeding in CiPu diets compared with CG and HMCS. There was no interaction between feed additive and energy source (P > 0.05) for any of the digestibility coefficients analyzed. Starch digestibility was less (P = 0.008) in PAP-MV when compared with CON and MON. In relation to energy sources, NDF digestibility was greater (P = 0.007) in CG and CiPu vs. the HMCS diet. The digestibility of ADF was greater (P = 0.002) in CiPu diets followed by CG and HMCS. Feeding PAP-MV or monensin altered ruminal fermentation patterns and digestive function in cows; however, those changes were independent of the main energy source of the diet.