Decreasing serum homocysteine and hypocholesterolemic effects of Bovine lactoferrin in male rat fed with high-cholesterol diet

Lactoferrin decorated bilosomes for the oral delivery of quercetin in type 2 diabetes: In vitro and in vivo appraisal

Despite its tremendous potential for type 2 diabetes management, quercetin (QRC) suffers poor gastric stability, poor bioavailability, and extensive first pass metabolism. Drug encapsulation into bilosomes (BSL) has proven enhanced properties in-vitro and in-vivo. Herein, this work endeavoured to evaluate efficacy of QRC-encapsulated bilosomes capped with lactoferrin (LF); a milk protein with antidiabetic potential, for type 2 diabetes oral treatment. The optimized formulation (LF-QRC-BSL) was evaluated in-vitro on α-amylase enzyme inhibition and insulin resistant HepG2 cell model and in vivo on streptozocin/high fat diet induced diabetes in rats. LF-QRC-BSL showed a small size (68.1 nm), a narrow PDI (0.18) and a -25.5 mV zeta potential. A high entrapment efficiency (94 %) with sustained release were also observed. LF-QRC-BSL displayed 100 % permeation through excised diabetic rat intestines after 6 h, 70.2 % inhibition of α-amylase enzyme in-vitro and an augmented recovery of glucose uptake in insulin resistant cells. In diabetic rats, LF-QRC-BSL resulted in significant decrease in blood glucose level, improved lipid profile and tissue injury markers with reduced oxidative stress and inflammatory markers. Further, histopathological examination of the kidneys, liver and pancreas revealed an almost restored normal condition comparable to the negative control. Overall, LF-QRC-BSL have proven to be a promising therapy for type 2 diabetes.

To Boost or to Reset: The Role of Lactoferrin in Energy Metabolism

Many pathological conditions, including obesity, diabetes, hypertension, heart disease, and cancer, are associated with abnormal metabolic states. The progressive loss of metabolic control is commonly characterized by insulin resistance, atherogenic dyslipidemia, inflammation, central obesity, and hypertension, a cluster of metabolic dysregulations usually referred to as the "metabolic syndrome". Recently, nutraceuticals have gained attention for the generalized perception that natural substances may be synonymous with health and balance, thus becoming favorable candidates for the adjuvant treatment of metabolic dysregulations. Among nutraceutical proteins, lactoferrin (Lf), an iron-binding glycoprotein of the innate immune system, has been widely recognized for its multifaceted activities and high tolerance. As this review shows, Lf can exert a dual role in human metabolism, either boosting or resetting it under physiological and pathological conditions, respectively. Lf consumption is safe and is associated with several benefits for human health, including the promotion of oral and gastrointestinal homeostasis, control of glucose and lipid metabolism, reduction of systemic inflammation, and regulation of iron absorption and balance. Overall, Lf can be recommended as a promising natural, completely non-toxic adjuvant for application as a long-term prophylaxis in the therapy for metabolic disorders, such as insulin resistance/type II diabetes and the metabolic syndrome.

Role of the protein kinase A signaling pathway and identification of mediators in the cardioprotective effects of enteral lactoferrin for ischemia-reperfusion injury in an isolated rat heart model

OBJECTIVE

Lactoferrin is an iron-binding glycoprotein. Enteral lactoferrin attenuates myocardial ischemia-reperfusion (IR) injury, but the underlying mechanism remains unknown. The aim of this study was to investigate protein kinase A (PKA) signaling pathway activation and levels of serum glucagonlike peptide-1 (GLP-1), secreted by intestinal endocrine L cells, and adiponectin, secreted by adipose tissue, after enteral lactoferrin administration.

METHODS

Hearts (N = 32) were excised from Wistar rats and perfused using a Langendorff system. To assess the role of the PKA pathway in the cardioprotective effects of lactoferrin, an inhibitor of PKA (H89) was applied before no-flow ischemia. Rats were randomly divided into four groups: control, lactoferrin (LF), control+H89, and LF+H89. The control and control+H89 groups were administered normal saline by gavage, and the LF and L +H89 groups were administered bovine lactoferrin (1000 mg/kg) by gavage 15 min before intraperitoneal pentobarbital injection. Muscle sampling was performed at the end of reperfusion. When rats were sacrificed, blood was sampled to measure hormone levels. The primary outcome was maximum left ventricular pressure derivative (LV dP/dt max) 15 min after reperfusion.

RESULTS

LV dP/dt max at 10 and 15 min after reperfusion was significantly higher in the LF group than in the control group (P < 0.05), and the effect was diminished by H89. The PKA pathway was significantly activated in the LF group. Enteral lactoferrin increased serum GLP-1 but not serum adiponectin levels.

CONCLUSIONS

Enteral lactoferrin induces cardioprotective effects against myocardial IR injury via the PKA signaling pathway and increases serum GLP-1 levels.

Lactoferrin-The Health-Promoting Properties and Contemporary Application with Genetic Aspects

The aim of the study is to present a review of literature data on lactoferrin's characteristics, applications, and multiple health-promoting properties, with special regard to nutrigenomics and nutrigenetics. The article presents a new approach to food ingredients. Nowadays, lactoferrin is used as an ingredient in food but mainly in pharmaceuticals and cosmetics. In the European Union, bovine lactoferrin has been legally approved for use as a food ingredient since 2012. However, as our research shows, it is not widely used in food production. The major producers of lactoferrin and the few available food products containing it are listed in the article. Due to anti-inflammatory, antibacterial, antiviral, immunomodulatory, antioxidant, and anti-tumour activity, the possibility of lactoferrin use in disease prevention (as a supportive treatment in obesity, diabetes, as well as cardiovascular diseases, including iron deficiency and anaemia) is reported. The possibility of targeted use of lactoferrin is also presented. The use of nutrition genomics, based on the identification of single nucleotide polymorphisms in genes, for example, FTO, PLIN1, TRAP2B, BDNF, SOD2, SLC23A1, LPL, and MTHFR, allows for the effective stratification of people and the selection of the most optimal bioactive nutrients, including lactoferrin, whose bioactive potential cannot be considered without taking into account the group to which they will be given.

Cardioprotective effects of enteral vs. parenteral lactoferrin administration on myocardial ischemia-reperfusion injury in a rat model of stunned myocardium

BACKGROUND

Lactoferrin, an iron-binding glycoprotein, is known to have protective effects against intestinal and cerebral ischemia-reperfusion (IR) injuries; however, its cardioprotective effects against the stunned myocardium are unknown. This study aimed to test the hypothesis that lactoferrin has cardioprotective effects against stunned myocardium.

METHODS

Using isolated rat hearts (Langendorff system), we determined the effects of lactoferrin administered enterally and by direct cardiac perfusion. Rat hearts were perfused using the Langendorff system, and two experiments were performed. In experiment 1, the hearts were divided into the enteral lactoferrin (E-LF) 7.5 m, 15 m, 30 m, and 60 m groups, where lactoferrin (1000 mg/kg) was administered enterally 7.5, 15, 30, and 60 min, respectively, before perfusion; and a control group, where saline was administered 30 min before perfusion. In experiment 2, hearts were allocated to the perfusate lactoferrin (P-LF) 15 and 100 groups, where 15 mg/L and 100 mg/L lactoferrin were respectively added to the perfusate, and a control group. Each group was perfused for 20 min prior to 15 min of no-flow ischemia with pacing, followed by 20 min of reperfusion. The primary outcome was the maximum left ventricular derivative of pressure development (LV dP/dt max) 15 min after reperfusion. Myocardial phospho-protein kinase B (p-Akt) was assayed using western blotting.

RESULTS

The LV dP/dt max 15 min after reperfusion in the E-LF 15 and 30 m groups was significantly higher than that in the control group. However, the effects disappeared in the E-LF 60 m group. In the second experiment, there were no significant differences in LV dP/dt max. Myocardial p-Akt was not significantly activated in any lactoferrin group.

CONCLUSION

Cardioprotection was observed 15-30 min after enteral lactoferrin but not by direct cardiac perfusion with lactoferrin. Myocardial p-Akt was not associated with the cardioprotective effect. The cardioprotective effect may be induced by enteral lactoferrin-induced substances.

The role of lactoferrin in atherosclerosis

Atherosclerosis (AS) is a common pathological basis for many cardiovascular diseases (CVDs) and result in high mortality and immense health and economic burdens worldwide. Early prevention, diagnosis, and treatment are promising approaches for stemming the development and progression of AS. Lactoferrin (Lf) is an iron-binding glycoprotein belonging to the transferrin family. It is widely found in body fluids such as digestive tract fluids, tears, and milk. Lf possesses anti-inflammatory, antibacterial, immunoregulatory, antioxidant and many other physiological functions. The serum Lf level is reportedly associated with the risk of AS and AS-related CVDs. Lf administration is closely involved in several mechanisms, including cholesterol metabolism, foam cell formation, ICAM-1 expression, homocysteine and leptin levels, anti-inflammatory and antioxidant function. Moreover, Lf has also been applied in the sythesis of magnetic resonance imaging (MRI) contrast agents to detect AS. Lf plays an important role in AS and may therefore be used in its diagnosis and treatment. Thus, this article aims to review the association between Lf and the risk of AS and AS-related CVDs, the mechanisms of Lf administration on AS, and its potential application in AS diagnosis.

Lactoferrin suppresses LPS-induced expression of HMGB1, microRNA 155, 146, and TLR4/MyD88/NF-кB pathway in RAW264.7 cells

OBJECTIVE

This current study evaluated the underlying mechanisms of LF against the inflammatory microRNAs (miRNAs), HMGB1 expression, and TLR4-MyD88-NF-кB pathway in LPS-activated murine RAW264.7 cells.

METHODS

MTT assay was used to assess cell metabolism and the cell culture levels of the cytokines (TNF-α, IL-6) were evaluated by Enzyme-linked immunosorbent assay (ELISA). The expression of miRNAs was quantified by using qPCR and the expression of HMGB1, TLR4, MyD88, and phosphorylated NF-κB (P-p65) were determined with Western blot and qPCR, respectively.

RESULTS

The results indicated that LF downregulates IL-6 and TNF-α expression. LF exhibited the degradation of P-p65 and reduced the production of HMGB1, TLR4, and MyD88 in LPS-induced inflammatory response. Importantly, in parallel with the suppression of cytokines and HMGB1-TLR4-MyD88-NF-кB pathway, LF could induce a decrease in inflammatory selected miRNAs, mmu-mir-155, and mmu-mir-146a expression.

CONCLUSIONS

Altogether, these findings provide LF as a prominent anti-inflammatory agent that could modulate HMGB1, mmu-mir-155, mmu-mir-146a, and TLR4/MyD88/NF-кB pathway.

Calcitriol modulates cholesteryl ester transfer protein (CETP) levels and lipid profile in hypercholesterolemic male rabbits: A pilot study

Vitamin D3 efficacy against cardiovascular disease prevention has been reported in many experimental studies. We aimed to investigate the effect of the calcitriol or active form of Vitamin D3 (1, 25(OH) 2D3) on serum cholesteryl ester transfer protein (CETP) levels in a rabbit model of atherosclerosis. New Zealand white male rabbits were fed with 1% cholesterol diet and randomly assigned into two groups (n = 6). The case group was administrated with 50000 calcitriol (IU/kg/per wk) and the control group which administrated with calcitriol solvent (sesame oil) for 2 months. Then, after two months the lipid profile, CETP and 25OHD3 levels were measured. The serum concentration of CETP was increased after treatment with calcitriol in case group as compared to the control group (41.75 ± 3.19 vs. 34.5 ± 2.3, ng/ml, P < 0.05). We also observed higher levels of the 25OHD3 in the calcitriol group at the 1^st month (16.3 ± 1.64 vs. 12.8 ± 1.33 ng/ml) and the 2^nd month (19.5 ± 2.14 vs. 12.5 ± 1.25 ng/ml) as compared with the control group. the significant increase in the level of HDL-C was observed in the case group than the control group (P < 0.01). In addition, serum levels of LDL- Cholesterol (LDL-C), Triglyceride (TG) were reduced after assessment at 1^st and 2^nd month after administration of calcitriol. Our research indicated the significant anti-atherogenic effects of calcitriol in the rabbit model of atherosclerosis. However, increased in CETP levels by calcitriol may know as an additional way, which interfere with the anti-atherogenic effects of calcitriol.

Lactoferrin promotes bile acid metabolism and reduces hepatic cholesterol deposition by inhibiting the farnesoid X receptor (FXR)-mediated enterohepatic axis

BACKGROUND

Lactoferrin (LF) is a multifunctional glycoprotein that can regulate lipid metabolism, lower cholesterol, reduce body weight, and prevent atherosclerosis. Bile acid (BA) metabolism plays an important role in removing excess cholesterol from the body. However, studies on the effects of LF on BA metabolism are limited and inconsistent.

METHODS

Male C57BL/6J mice aged 6-8 weeks were fed with a normal diet (control group), high-fat/high-cholesterol diet containing cholate (HFCCD group), or HFCCD and 1.0% LF in drinking water (LF group) for 8 weeks. Serum and hepatic lipid profiles, and glucose tolerance were measured. Fecal BA composition was determined through ultra-high performance liquid chromatography-tandem mass spectrometry. The gene expression of BA synthase in the liver and farnesoid X receptor (FXR)-mediated BA negative feedback regulation pathway in the liver and ileum were analyzed via RNA analysis.

RESULTS

HFCCD resulted in abnormal cholesterol levels in the serum and liver. LF intervention significantly increased the serum high-density lipoprotein cholesterol level by 24.9% and decreased the hepatic total cholesterol content by 26%. LF treatment significantly increased the BA content per gram by 109.8%, the total amount of BA excretion by 153.5% and conjugated BAs by 87.6% in the feces. Furthermore, LF upregulated the expression of the hepatic sterol 12α-hydroxylase (CYP8B1) gene, which expresses important enzymes in the classical pathway of BA synthesis, and the bile acid-CoA amino acid N-acetyltransferase (BAAT) gene, which is responsible for the formation of conjugated BAs. The FXR-mediated pathways in the enterohepatic axis, including FXR, fibroblast growth factor 15, and fibroblast growth factor receptor 4, were inhibited by LF.

CONCLUSIONS

LF ameliorated hepatic cholesterol deposition in mice fed with a high-fat and high cholesterol diet containing cholate. LF elevated the conjugated BA level, inhibited the ileum FXR and FXR-mediated enterohepatic axis, and increased BA synthesis and excretion.

Bovine lactoferrin ameliorates antioxidant esterase activity and 8-isoprostane levels in high-cholesterol-diet fed rats

Abstract. The main aim of the present study was to show the effect of bovineLactoferrin (bLF), an 80 kD iron-binding glycoprotein, its application on antioxidant esterase activities and 8-isoprostane changes in high-cholesterol-diet fed (HCD-Fed) rats. The 44 adult Sprague-Dawley male rats were randomly assigned into four experimental groups. They were randomly assigned into four equivalent groups (n = 11). The groups included the control group which was fed with normal diet, bLF group, the third group which were made hypercholesterolemia by being fed with high cholesterol diet, and the last group which consisted of hypercholesterolemia rats treated with bLF (HCD + bLF) for 4 weeks (200 mg.kg−1 per day wt. dissolved in 0.9% normal saline).After 4 weeks, the serum Paraoxonase1 (PON1), Arylesterase (ARE) activity and 8-isoprostane with lipid profile were measured. Upon treatment with the bLF, the decrease in LDL-Cholesterol (LDL-C), Glucoses, Triglyceride (TG) and Total-Cholesterol (TC) levels and an increase in HDL-Cholesterol (HDL-C) level were observed. The co-administration of bLf for 4 weeks had decreased the 8-isoprostane levels significantly (P < 0.001) (86.36 ± 7.1 vs 117.18 ± 8.62) when compared to hypercholesterolemia-induced rats. Also, the Atherogenic Index (AI) in HCD + bLF group showed a significant decrease as compared to the HCD group (P < 0.001) (0.37 ± 0.07 vs 0.57 ± 0.09). The results indicated that bLF was effective against oxidative stress by its ability to increase PON1 activity and reduce the lipid peroxidation in high-cholesterol-fed rats.