Plant polyphenols mechanisms of action on insulin resistance and against the loss of pancreatic beta cells.

Diabetes mellitus describes a group of metabolic disorders characterized by a prolonged period hyperglycemia with long-lasting detrimental effects on the cardiovascular and nervous systems, kidney, vision, and immunity. Many plant polyphenols are shown to have beneficial activity for the prevention and treatment of diabetes, by different mechanisms. This review article is focused on synthesizing the mechanisms by which polyphenols decrease insulin resistance and inhibit loss of pancreatic islet ß-cell mass and function. To achieve the objectives, this review summarizes the results of the researches realized in recent years in clinical trials and in various experimental models, on the effects of foods rich in polyphenols, polyphenolic extracts, and commercially polyphenols on insulin resistance and ß-cells death. Dietary polyphenols are able to reduce insulin resistance alleviating the IRS-1/PI3-k/Akt signaling pathway, and to reduce the loss of pancreatic islet ß-cell mass and function by several molecular mechanisms, such as protection of the surviving machinery of cells against the oxidative insult; increasing insulin secretion in pancreatic ß-cells through activation of the FFAR1; cytoprotective effect on ß-cells by activation of autophagy; protection of ß-cells to act as activators for anti-apoptotic pathways and inhibitors for apoptotic pathway; stimulating of insulin release, presumably by transient ATP-sensitive K+ channel inhibition and whole-cell Ca2+ stimulation; involvement in insulin release that act on ionic currents and membrane potential as inhibitor of delayed-rectifier K+ current (IK(DR)) and activator of current. dietary polyphenols could be used as potential anti-diabetic agents to prevent and alleviate diabetes and its complications, but further studies are needed.

Erratum: Aluwé, M. et al. Exploratory Survey on European Consumer and Stakeholder Attitudes towards Alternatives for Surgical Castration of Piglets. Animals 2020, 10, 1758.

The authors wish to make the following corrections to this paper [...].

Exploratory Survey on European Consumer and Stakeholder Attitudes towards Alternatives for Surgical Castration of Piglets.

Surgical castration of piglets without pain relief is still common practice in many countries. Possible alternatives for surgical castration are application of pain relief or anaesthesia or production of boars (entire males) and immunocastrates. Each of these alternatives faces advantages and disadvantages which may result in different citizen attitudes and consumers acceptability. Understanding which practice is acceptable to whom and why may further stimulate implementation. Consumer (n = 3251) and stakeholder (n = 1027) attitudes towards surgical castration without pain relief, surgical castration with anaesthesia, immunocastration, and production of boars were surveyed from April to June 2020 via an online questionnaire in 16 countries (>175 respondents per country). Surgical castration without pain relief was separated from each of the alternatives due to animal welfare and showed the lowest acceptability (32%). Within the alternatives, a further partitioning between the alternatives was based on perceived quality and food safety, with an acceptance of 85% for applying anaesthesia, 71% for immunocastration, and 49% for boar production. Differences depending on professional involvement and familiarity with agriculture could be observed, mainly for the acceptance of surgical castration without anaesthesia, immunocastration, and boars. Castration with anaesthesia was highly accepted by all types of respondents.

Attitudes and Beliefs of Eastern European Consumers Towards Animal Welfare.

The aim of this exploratory work, because of the existing bias on the size of the sample and some of the sociodemographic characteristics of the participants, was to investigate the Eastern European consumers' beliefs and attitudes toward animal welfare, to perform a cross-country segmentation analysis and to observe possible differences with their Western European counterparts. For this purpose, a survey was conducted with 5508 consumers from 13 Eastern European countries (Bosnia and Herzegovina, Bulgaria, Czech Republic, Croatia, North Macedonia, Hungary, Moldova, Poland, Romania, Serbia, Slovakia, Slovenia, and Ukraine) using a questionnaire with nine statements about consumers beliefs regarding animal welfare (aspects of management, ethical issues about animals, and consequences of animal welfare on meat quality and price), one statement about the willingness to pay more for meat produced under better welfare conditions, and four statements regarding attitudes toward animal welfare. Differences between countries were detected for all the statements. Moreover, three clusters of consumers were identified: one with consumers indifferent towards animal welfare; one with consumers concerned about animal welfare, but they believe it is difficult to achieve; and one with consumers concerned about animal welfare, and they believe it is possible to achieve it.

Attitudes and beliefs of Eastern European consumers towards piglet castration and meat from castrated pigs.

Castration of male piglets is a common practice to avoid boar taint but is being questioned. The present work has an exploratory character and aims to investigate the beliefs and attitudes of Eastern European consumers regarding boar taint, surgical castration immunocastration and perception of meat from castrated pigs and to find out possible segments of consumers regarding these attitudes and beliefs. For this purpose, a consumer study was carried out involving 5508 consumers from 13 Eastern European countries (Bosnia and Herzegovina, Bulgaria, Czech Republic, Croatia, North Macedonia, Hungary, Moldova, Poland, Romania, Serbia, Slovakia, Slovenia and Ukraine). The questionnaire included statements related to beliefs about castration and perception of meat from castrated pigs, attitudes towards meat from castrated pigs. Results show that in general beliefs and attitudes of the consumers are not defined, probably because of the lack of knowledge (information was not provided to the consumers) towards these issues. Three different clusters of consumers were obtained with different beliefs towards castration.

Bioavailability of Quercetin in Humans with a Focus on Interindividual Variation.

After consumption of plant-derived foods or beverages, dietary polyphenols such as quercetin are absorbed in the small intestine and metabolized by the body, or they are subject to catabolism by the gut microbiota followed by absorption of the resulting products by the colon. The resulting compounds are bioavailable, circulate in the blood as conjugates with glucuronide, methyl, or sulfate groups attached, and they are eventually excreted in the urine. In this review, the various conjugates from different intervention studies are summarized and discussed. In addition, the substantial variation between different individuals in the measured quercetin bioavailability parameters is assessed in detail by examining published human intervention studies where sources of quercetin have been consumed in the form of food, beverages, or supplements. It is apparent that most reported studies have examined quercetin and/or metabolites in urine and plasma from a relatively small number of volunteers. Despite this limitation, it is evident that there is less interindividual variation in metabolites which are derived from absorption in the small intestine compared to catabolites derived from the action of microbiota in the colon. There is also some evidence that a high absorber of intact quercetin conjugates could be a low absorber of microbiota-catalyzed phenolics, and vice versa. From the studies reported so far, the reasons or causes of the interindividual differences are not clear, but, based on the known metabolic pathways, it is predicted that dietary history, genetic polymorphisms, and variations in gut microbiota metabolism would play significant roles. In conclusion, quercetin bioavailability is subject to substantial variation between individuals, and further work is required to establish if this contributes to interindividual differences in biological responses.

Comparative study of the influence of hawthorn (Crataegus monogyna) berry ethanolic extract and butylated hydroxylanisole (BHA) on lipid peroxidation, myoglobin oxidation, consistency and firmness of minced pork during refrigeration.

BACKGROUND: Following public concern on the use of synthetic food antioxidants, there is an increasing demand for the application of mixed or purified natural antioxidants to maintain quality of meat products quality during storage. The aim of this research was to investigate the effect of ethanolic extract of hawthorn berry, compared to butylated hydroxylanisole (BHA), on lipid peroxidation, myoglobin oxidation, protein electrophoresis pattern, consistency and firmness of minced pork during refrigeration at 4 °C, and to identify the relationship between chemical modifications and consistency variation. RESULTS: After 6 days of refrigeration it was found that the thiobarbituric acid reactive substances value of minced pork containing 200 mg GAE kg-1 total phenolics in minced meat (200 HP) was significantly lower (0.1543 ± 0.006 mg) compared to BHA-treated meat. The ratio of oxymyoglobin to metmyoglobin in treated minced pork was respectively 0.845 for 200 HP and 0.473 for BHA-treated minced meat. Concentrations of 100 HP or 300 HP will generate statistically higher firmness than BHA in minced pork. CONCLUSION: Hawthorn berry ethanolic extract was more effective than BHA in reducing lipid oxidation and protein degradation, for maintaining firmness and consistency of minced pork during 6 days of refrigeration at 4 °C. © 2017 Society of Chemical Industry.

Comparative study of mineral composition of beef steak and pork chops depending on the thermal preparation method.

This study focuses on the effects of three different thermal preparation methods (roasting, boiling, and microwave cooking) on the mineral concentrations of beef and pork, as well as on the comparison of mineral levels between these two types of meat. In this study, raw and cooked beef and pork samples were selected and analyzed by ICP-OES in order to determine mineral concentrations. In general, thermal preparation clearly increased mineral concentrations in cooked samples compared to raw meat. The highest mineral concentration was identified in the roasted samples. Trace element concentrations in beef were significantly higher compared to pork. In pork, Na concentration decreased in all samples, suggesting that Na is lost with water. Zn mean content in cooked beef samples registered significant differences compared to pork cooked samples. The percentage of water loss during the microwave thermal preparation for beef samples was higher than the other two treatments.

A model of cadmium accumulation in the liver and kidney of sheep derived from soil and dietary characteristics.

BACKGROUND: Cadmium accumulates in sheep tissues and often approaches the legal limit for human consumption in kidneys. Previous models have focused on transfer from plants to sheep but have restricted value due to seasonal and species variation in plant cadmium concentration. We created a model for the accumulation of cadmium in sheep using empirical relationships previously derived for accumulation in sheep kidney and liver from feeds, together with equations for accumulation in feeds derived from soil characteristics. The combined model relates soil cadmium to liver and kidney concentrations. RESULTS: Sensitivity analysis demonstrated that the kidney accumulated cadmium faster than the liver and the greatest influence was the total cadmium concentration in the soil. The weight gain of the sheep and soil pH where the feed was grown had relatively minor influences on cadmium concentration in liver or kidney. CONCLUSION: A combined model of soil, plant and sheep kidney and liver characteristics enables concentrations of cadmium in sheep liver and kidney to be predicted from soil characteristics. This will enable the long-term risks of specific sites to be predicted with greater accuracy than if just plant cadmium concentrations were utilized.