Influence of 4-week intraduodenal supplementation of quercetin on performance, glucose metabolism, and mRNA abundance of genes related to glucose metabolism and antioxidative status in dairy cows.
Quercetin has been shown to be a potent antioxidant, acts hepatoprotectively, and affects glucose and lipid metabolism in monogastrics. If this is also true in ruminants, quercetin could be beneficial in periparturient high-yielding dairy cows by ameliorating the negative effects of free radical formation and reducing the severity of liver lipidosis and ketosis. In a first attempt to evaluate effects of a long-term quercetin treatment, we intraduodenally administered twice daily 18 mg of quercetin (Q)/kg of body weight to 5 late-lactation (215d in milk) dairy cows over a period of 28 d. Frequent blood samples were taken before and during administration to determine plasma concentrations of flavonols and metabolites. Before and after 1 and 4 wk of Q administration, glycogen and fat content as well as mRNA expression of selected genes were measured in liver biopsies. Furthermore, euglycemic, hyperinsulinemic, and hyperglycemic clamp studies were conducted before and after 2 wk of Q administration. During the experiment, dry matter intake and most other zootechnical data remained unchanged. Milk protein content was increased in wk 2 and 4 of Q administration compared with basal values, whereas fat and lactose contents of milk remained unchanged. Plasma nonesterified fatty acids, γ-glutamyl transferase, cholesterol, glutamate dehydrogenase, triglyceride, and albumin concentrations, as well as liver fat and glycogen concentrations, were not affected by Q supplementation. Plasma glucose and β-hydroxybutyrate concentrations in plasma decreased and increased, respectively, under the influence of quercetin. During hyperglycemic clamp conditions, the relative increase of plasma insulin was higher after 2 wk of Q administration, and a tendency for an increased rQUICKI (revised quantitative insulin sensitivity check index) was observed. The relative mRNA expression levels of selected genes related to glucose metabolism, fat metabolism, and antioxidative status were not altered after 1 or 4 wk of Q supplementation. In conclusion, the effects on insulin release and sensitivity support the assumption that administration of Q could have positive effects on the metabolic adaption of high-yielding cows to early lactation. The increase of milk protein content in response to Q supplementation needs to be verified.
Institute of Nutritional Physiology "Oskar Kellner,", Dummerstorf, Germany.
A
A
Gohlke
Institute of Nutritional Physiology "Oskar Kellner,", Dummerstorf, Germany.
C J
CJ
Ingelmann
Institute of Genetics and Biometry, Dummerstorf, Germany.
G
G
Nürnberg
Institute of Reproductive Biology, Leibniz Institute for Farm Animal Biology (FBN), 18196 Dummerstorf, Germany.
J M
JM
Weitzel
Institute of Nutritional Physiology "Oskar Kellner,", Dummerstorf, Germany.
H M
HM
Hammon
Institute of Nutritional Physiology "Oskar Kellner,", Dummerstorf, Germany.
S
S
Görs
Clinic for Cattle, School of Veterinary Medicine Hannover, 30173 Hannover, Germany.
A
A
Starke
Institute of Animal Nutrition and Physiology, Christian-Albrechts-University of Kiel, 24118 Kiel, Germany.
S
S
Wolffram
Institute of Nutritional Physiology "Oskar Kellner,", Dummerstorf, Germany. Electronic address: metges@fbn-dummerstorf.de.
C C
CC
Metges
D020155:3-Hydroxybutyric Acid / Q000097:blood; D000818:Animals; D000975:Antioxidants; D001786:Blood Glucose / Q000235:genetics / Q000378:metabolism*; D002417:Cattle / Q000378:metabolism*; D019587:Dietary Supplements; D004386:Duodenum / Q000187:drug effects*; D004734:Energy Metabolism / Q000502:physiology; D005260:Female; D044948:Flavonols / Q000097:blood; D015309:Glucose Clamp Technique; D007328:Insulin / Q000097:blood / Q000378:metabolism; D000078790:Insulin Secretion; D007774:Lactation / Q000502:physiology; D008099:Liver / Q000737:chemistry / Q000378:metabolism; D008892:Milk / Q000737:chemistry; D008894:Milk Proteins / Q000032:analysis; D011794:Quercetin / Q000008:administration & dosage*; D012333:RNA, Messenger / Q000032:analysis* / Q000378:metabolism
D000975:Antioxidants; D001786:Blood Glucose; D044948:Flavonols; D007328:Insulin; D008894:Milk Proteins; D012333:RNA, Messenger; D011794:Quercetin; D020155:3-Hydroxybutyric Acid
antioxidative status; duodenal cannula; glucose production; quercetin