Different techniques to evaluate a liquid rumen protected methionine source for dairy cows

Rumen protected methionine has been used in an effort to improve the amino acid composition of metabolisable protein since the early 1960’s. The positive response in dairy cows in terms of milk protein composition and milk production, especially during early lactation has been well documented. Rumen protected methionine supplementation contributes to improving the protein efficiency of the dairy cow which improves the overall productivity of the dairy enterprise. Recently a locally developed liquid rumen protected methionine prototype became available. In our study this product was evaluated through a series of experiments in conjunction with two standard, well known methionnine sources, Smartamine ™ M and unprotected DL-methionine that provided a reference to the relative bioavailability of the liquid rumen protected methionine. In the first of the two studies the effect of methionine supplementation on milk yield, milk composition as well as milk protein composition was evaluated through the milk composition technique. The ability of the liquid rumen protected methionine to elevate blood plasma methionine levels was also evaluated through the blood plasma technique after oral dosing and post ruminal infusion of methionine. The liquid rumen protected methionine prototype induced no response in either milk yield or milk composition. Results suggested that the prototype is either not adequately protected against rumen degradation or it is not available for absorption in the small intestine. The inability of the liquid rumen protected methionine prototype to elevate blood plasma methionine after post ruminal infusion further proved that the product is not available for absorption at this site either. In the event that the product’s mode of action or method of protection caused it not to be detected as pure methionine in the blood, an effect on milk yield would have been expected which was not the case. This product proved to have a very low or no bioavailability in comparison to the well researched and proven Smartamine ™ M.Dissertation (MSc(Agric))--University of Pretoria, 2012.Animal and Wildlife Sciencesunrestricte

Inhibition of α-glucosidase and α-amylase by herbal compounds for the treatment of type 2 diabetes : a validation of in silico reverse docking with in vitro enzyme assays

BACKGROUND : α-Amylase and α-glucosidase are important therapeutic targets for the management of type 2 diabetes mellitus. The inhibition of these enzymes decreases postprandial hyperglycemia. In the present study, compounds found in commercially available herbs and spices were tested for their ability to inhibit α-amylase and α-glucosidase. These compounds were acetyleugenol, apigenin, cinnamic acid, eriodictyol, myrcene, piperine, and rosmarinic acid. METHODS : The enzyme inhibitory nature of the compounds was evaluated using in silico docking analysis with Maestro software and was further confirmed by in vitro α-amylase and α-glucosidase biochemical assays. RESULTS : The relationships between the in silico and in vitro results were well correlated; a more negative docking score was associated with a higher in vitro inhibitory activity. There was no significant (P > .05) difference between the inhibition constant (Ki) value of acarbose, a widely prescribed α-glucosidase and α-amylase inhibitor, and those of apigenin, eriodictyol, and piperine. For α-amylase, there was no significant (P > .05) difference between the Ki value of acarbose and those of apigenin, cinnamic acid, and rosmarinic acid. The effect of the herbal compounds on cell viability was assessed with the sulforhodamine B (SRB) assay in C2C12 and HepG2 cells. Acetyleugenol, cinnamic acid, myrcene, piperine, and rosmarinic acid had similar (P > .05) IC50 values to acarbose. CONCLUSIONS : Several of the herbal compounds studied could regulate postprandial hyperglycemia. Using herbal plants has several advantages including low cost, natural origin, and easy cultivation. These compounds can easily be consumed as teas or as herbs and spices to flavor food.SUPPLEMENTARY MATERIAL : Figure S1 Lineweaver-Burk graphs of the inhibition of α-amylase by herbal compounds (n = 3, SD error bars). Figure S2. Lineweaver-Burk graphs of the inhibition of α-glucosidase by herbal compounds (n = 3, SD error bars). Figure S3. Viability of C2C12 cells after 72 hours exposure to acarbose (control) and herbal compounds (n = 3, SD error bars). Figure S4. Viability of HepG2 cells after 72 hours exposure to acarbose (control) and herbal compounds (n = 3, SD error bars). Table S1. Michaelis-Menten parameters for the inhibition of α-amylase by herbal compounds. Table S2. Michaelis-Menten parameters for the inhibition of α-glucosidase by herbal compounds.The University of Pretoria with a postgraduate scholarship.http://wileyonlinelibrary.com/journal/jdbhj2022AnatomyBiochemistryGeneticsMicrobiology and Plant Patholog

Exploring the anti-proliferative activity of Pelargonium sidoides DC with in silico target identification and network pharmacology

Pelargonium sidoides DC (Geraniaceae) is a medicinal plant indigenous to Southern Africa that has been widely evaluated for its use in the treatment of upper respiratory tract infections. In recent studies, the anti-proliferative potential of P. sidoides was shown, and several phenolic compounds were identified as the bioactive compounds. Little, however, is known regarding their anti-proliferative protein targets. In this study, the anti-proliferative mechanisms of P. sidoides through in silico target identification and network pharmacology methodologies were evaluated. The protein targets of the 12 phenolic compounds were identified using the target identification server PharmMapper and the server for predicting Drug Repositioning and Adverse Reactions via the Chemical–Protein Interactome (DRAR-CPI). Protein–protein and protein–pathway interaction networks were subsequently constructed with Cytoscape 3.4.0 to evaluate potential mechanisms of action. A total of 142 potential human target proteins were identified with the in silico target identification servers, and 90 of these were found to be related to cancer. The protein interaction network was constructed from 86 proteins involved in 209 interactions with each other, and two protein clusters were observed. A pathway enrichment analysis identified over 80 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways enriched with the protein targets and included several pathways specifically related to cancer as well as various signaling pathways that have been found to be dysregulated in cancer. These results indicate that the anti-proliferative activity of P. sidoides may be multifactorial and arises from the collective regulation of several interconnected cell signaling pathways.https://link.springer.com/journal/110302018-11-18hj2017AnatomyBiochemistr

Milk composition as technique to evaluate the relative bioavailability of a liquid rumen protected methionine source

Rumen protected amino acids (RPAA) are increasingly being used in dairy cattle diet formulation to obtain the required concentrations of lysine and methionine in metabolisable protein for optimal milk and milk protein production. The objective of this study was to evaluate the relative bioavailability of a liquid rumen protected lysine prototype using the milk composition technique. Forty mid-lactation Holstein cows were used in a complete randomised block design experiment and allocated to one of four experimental treatments. The treatments were: (1) Methionine deficient (Met-) diet, (2) Met- diet supplemented with Smartamine M (SMM), (3) Met- diet supplemented with liquid rumen protected prototype (LRPMet) and (4) Met- diet supplemented with DL Met (DLMet), a hydroxyl analogue of methionine. After an adaptation phase all four groups received the Met- diet and thereafter switched over to the four treatments. Cows supplemented with SMM had higher milk protein and milk fat % compared to the other treatments and increased milk casein % significantly when compared to the Met-control treatment. The milk protein percentages were 3.06, 3.25, 2.95 and 3.46 and the milk fat percentages 3.84, 3.93, 3.75 and 4.27 for the Met-, LRPMet, DL Met and SMM treatments, respectively. SMM again proved to be the RPAA with a high relative bioavailability, while the LRPMet failed to elicit any milk yield or milk composition response. The milk composition technique proved to be a simple but effective technique to evaluate the bioavailability of rumen protected products or prototypes.http://www.sasas.co.za/am201

Anti-proliferative properties of commercial Pelargonium sidoides tincture, with cell-cycle G(0)/G(1) arrest and apoptosis in Jurkat leukaemia cells

CONTEXT : Pelargonium sidoides DC (Geraniaceae) is an important medicinal plant indigenous to South Africa and Lesotho. Previous studies have shown root extracts rich in polyphenolic compounds with antibacterial, antiviral and immunomodulatory activities. Little is known regarding the anticancer properties of Pelargonium sidoides extracts. OBJECTIVE : This study evaluates the anti-proliferative effects of a Pelargonium sidoides radix mother tincture (PST). MATERIALS AND METHODS : The PST was characterized by LC-MS/MS. Anti-proliferative activity was evaluated in the pre-screen panel of the National Cancer Institute (NCI-H460, MCF-7 and SF-268) and the Jurkat leukemia cell line at concentrations of 0-150 μg/mL. Effect on cell growth was determined with sulforhodamine B and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays after 72 h. Effect on cell cycle and apoptosis induction in Jurkat cells was determined by flow cytometry with propidium iodide and Annexin V: fluorescein isothiocyanate staining. RESULTS : Dihydroxycoumarin sulfates, gallic acid as well as gallocatechin dimers and trimers were characterized in PST by mass spectrometry. Moderate anti-proliferative effects with GI50 values between 40 and 80 μg/mL observed in the NCI-pre-screen panel. Strong activity observed with Jurkat cells with a GI50 of 6.2 μg/mL, significantly better than positive control 5-fluorouracil (GI50 of 9.7 μg/mL). The PST arrested Jurkat cells at G0/G1 phase of the cell cycle and increased the apoptotic cells from 9% to 21%, while the dead cells increased from 4% to 17%. CONCLUSION : We present evidence that Pelargonium sidoides has cancer cell type specific antiproliferative effects and may be a source of novel anticancer molecules.National Research Foundation of South Africa.http://www.tandfonline.com/loi/iphb202017-09-30hb2016AnatomyBiochemistr

Activity-guided isolation and identification of the major antioxidant and anticancer compounds from a commercial Pelargonium sidoides tincture

Extracts prepared from the roots of Pelargonium sidoides (DC) are commercially available for the treatment of respiratory related conditions. Recently, a commercial radix mother tincture of this plant was shown to have both antioxidant and anticancer effects especially related to the G0/G1 block in the Jurkat E6.1 cell line (unpublished results). Fractions were prepared by semi-preparative HPLC, and their antioxidant and anticancer activities were determined. The more hydrophilic fractions isolated namely F6-F12 were all found to have strong reducing capacities and were able to scavenge peroxyl radicals. In the human lung cell line, NCI-H460, significant cellular antioxidant effects were observed. Anticancer activity was evaluated in the NCI-pre-screen panel (NCI-H460, MCF-7 and SF-268) and the Jurkat E6.1 cell line. Fractions F7, F9 and F12 were found to inhibit the cell growth of these four cell-lines (p < 0.05), especially the Jurkat E6.1 cell line with the sulforhodamine B assay. Mass spectrometry analysis revealed that these active fractions contained several polyphenolic compounds such as gallic acid, trihydroxycoumarin, dihydroxycoumarin sulfates, proanthocyanidins and phenolic glycosides. A phenolic acid glycoside sulfate not previously shown in Pelargonium sidoides extracts was also isolated. In conclusion, the antioxidant and/or anticancer activity of the Pelargonium sidoides tincture may be attributed to the presence of these polyphenolics.National Research Foundation of South Africahttp://link.springer.com/journal/442016-11-30hb201

Antioxidant and anti-inflammatory properties of Ilex guayusa tea preparations : a comparison to Camellia sinensis teas

Ilex guayusa tea preparations are now commercially available as Runa tea. Little is known regarding the antioxidant and anti-inflammatory bioactivities of this tea. The I. guayusa teas had a total polyphenolic content between 54.39 and 67.23 mg GAE/g dry mass and peroxyl radical scavenging capacities between 1773.41 and 2019 µmol TE/g dry mass, nearly half of that for the Camellia sinensis teas. The I. guayusa teas afforded 60-80% protection from oxidative stress in the Caco-2 cellular antioxidant assay, comparable to the C. sinensis teas. The anti-inflammatory activity in lipopolysaccharide-stimulated RAW 264.7 cells of I. guayusa teas was similarly comparable to the C. sinensis teas with nitric oxide production reduced by 10-30%. Major compounds identified by mass spectrometry were the phenolic mono- and dicaffeoylquinic acid derivatives. I. guayusa teas are a good source of dietary phenolic compounds with cellular antioxidant and anti-inflammatory properties.http://pubs.rsc.org/en/journals/journalissues/fo#!recentarticles&adv2018-12-13hj2017AnatomyBiochemistr

In-silico reverse docking and in-vitro studies identified curcumin, 18α-glycyrrhetinic acid, rosmarinic acid, and quercetin as inhibitors of α-glucosidase and pancreatic α-amylase and lipid accumulation in HepG2 cells, important type 2 diabetes targets

Please read abstract in the article.The National Research Foundation (NRF) of South Africa.http://www.elsevier.com/locate/molstr2023-06-22hj2023AnatomyBiochemistryGeneticsMicrobiology and Plant Patholog

Targeting the Hindgut to Improve Health and Performance in Cattle

An adequate gastrointestinal barrier function is essential to preserve animal health and well-being. Suboptimal gut health results in the translocation of contents from the gastrointestinal lumen across the epithelium, inducing local and systemic inflammatory responses. Inflammation is characterized by high energetic and nutrient requirements, which diverts resources away from production. Further, barrier function defects and inflammation have been both associated with several metabolic diseases in dairy cattle and liver abscesses in feedlots. The gastrointestinal tract is sensitive to several factors intrinsic to the productive cycles of dairy and beef cattle. Among them, high grain diets, commonly fed to support lactation and growth, are potentially detrimental for rumen health due to their increased fermentability, representing the main risk factor for the development of acidosis. Furthermore, the increase in dietary starch associated with such rations frequently results in an increase in the bypass fraction reaching distal sections of the intestine. The effects of high grain diets in the hindgut are comparable to those in the rumen and, thus, hindgut acidosis likely plays a role in grain overload syndrome. However, the relative contribution of the hindgut to this syndrome remains unknown. Nutritional strategies designed to support hindgut health might represent an opportunity to sustain health and performance in bovines