Identification of unprecedented anticancer properties of high molecular weight biomacromolecular complex containing bovine lactoferrin (HMW-bLf)

The Multifaceted Roles of Bovine Lactoferrin: Molecular Structure, Isolation Methods, Analytical Characteristics, and Biological Properties

Bovine lactoferrin (bLF) is widely known as an iron-binding glycoprotein from the transferrin family. The bLF molecule exhibits a broad spectrum of biological activity, including iron delivery, antimicrobial, antiviral, immunomodulatory, antioxidant, antitumor, and prebiotic functions, thereby making it one of the most valuable representatives for biomedical applications. Remarkably, LF functionality might completely differ in dependence on the iron saturation state and glycosylation patterns. Recently, a violently growing demand for bLF production has been observed, mostly for infant formulas, dietary supplements, and functional food formulations. Unfortunately, one of the reasons that inhibit the development of the bLF market and widespread protein implementation is related to its negligible amount in both major sources─colostrum and mature milk. This study provides a comprehensive overview of the significance of bLF research by delineating the key structural characteristics of the protein and elucidating their impact on its physicochemical and biological properties. Progress in the development of optimal isolation techniques for bLF is critically assessed, alongside the challenges that arise during its production. Furthermore, this paper presents a curated list of the most relevant instrumental techniques for the characterization of bLF. Lastly, it discusses the prospective applications and future directions for bLF-based formulations, highlighting their potential in various fields.

Invited review: Properties of β-galactosidases derived from Lactobacillaceae species and their capacity for galacto-oligosaccharide production

β-galactosidase (enzymatic class 3.2.1.23) is one of the dairy industry's most important and widely used enzymes. The enzyme is part of a large family known to catalyze hydrolysis and transglycosylation reactions. Its hydrolytic activity is commonly used to decrease lactose content in dairy products, while its transglycosylase activity has recently been used to synthesize galacto-oligosaccharides (GOS). During the past couple of years, researchers have focused on studying β-galactosidase isolated and purified from lactic acid bacteria. This review will focus on β-galactosidase purified and characterized from what used to be the Lactobacillus genera. Furthermore, particular emphasis is given to its kinetics, biochemical characteristics, GOS production, market, and utilization by Lactobacilllaceae species.

Anticancer activity of lactoferrin-coated biosynthesized selenium nanoparticles for combating different human cancer cells via mediating apoptotic effects

The present study aims to develop a novel nanocombination with high selectivity against several invasive cancer cells, sparing normal cells and tissues. Bovine lactoferrin (bLF) has recently captured the interest of numerous medical fields owing to its biological activities and well-known immunomodulatory effects. BLF is an ideal protein to be encapsulated or adsorbed into selenium nanocomposites (Se NPs) in order to produce stable nanocombinations with potent anticancer effects and improved immunological functions. The biosynthesis of the functionalized Se NPs was achieved using Rhodotorula sp. strain MZ312359 via a simultaneous bio-reduction approach to selenium sodium salts. The physicochemical properties of Se NPs using SEM, TEM, FTIR, UV Vis, XRD, and EDX confirmed the formation of uniform agglomerated spheres with a size of 18-40 nm. Se NPs were successfully embedded in apo-LF (ALF), forming a novel nanocombination of ALF-Se NPs with a spherical shape and an average nanosize of less than 200 nm. The developed ALF-Se NPs significantly displayed an effective anti-proliferation efficiency against many cancer cells, including MCF-7, HepG-2, and Caco-2 cell lines, as compared to Se NPs and ALF in free forms. ALF-Se NPs showed a significant selectivity impact (> 64) against all treated cancer cells at IC₅₀ 63.10 ≤ μg/mL, as well as the strongest upregulation of p53 and suppression of Bcl-2, MMP-9, and VEGF genes. Besides, ALF-Se NPs were able to show the maximum activation of transcrition of key redox mediator (Nrf2) with suppression in reactive oxygen species (ROS) levels inside all treated cancer cells. This study demonstrates that this novel nanocombination of ALF-Se NPs has superior selectivity and apoptosis-mediating anticancer activity over free ALF or individual form of Se NPs.

Lactoferrin: A Nutraceutical with Activity against Colorectal Cancer

Homeostasis in the human body results from the tight regulation of several events, since too little inflammation disrupts the process of tissue repair and remodeling, whereas too much exerts a collateral effect by causing tissue damage with life-threatening consequences. In some clinical conditions, such as inflammatory bowel disease (IBD), inflammation functions as a double-edged sword by either enabling or inhibiting cancer development and progression. Generally, cancer develops through evasion mechanisms that regulate cell growth, causing a high rate of uncontrolled proliferation, and mechanisms for evading cell death, such as apoptosis. Moreover, chronic inflammation is a factor that contributes to colorectal cancer (CRC), as observed in individuals with IBD; all these conditions favor an increased rate of angiogenesis and eventual metastasis. Lactoferrin (Lf) is a mammalian iron-binding multifunctional glycoprotein regarded as a natural compound that up- and downregulates both humoral and cellular components of immunity involved in regulating the inflammatory response and maintaining gut homeostasis. Human and bovine Lf share high sequence homology and have very similar antimicrobial, anti-inflammatory, and immunomodulatory activities. Bovine Lf from milk is considered a safe molecule and is commercially available in large quantities. This review mainly focuses on the regulatory effects of orally administered bovine Lf on the inflammatory response associated with CRC; this approach indicates that CRC is one of the most frequently diagnosed cancers and affects the intestinal tract with high clinical and epidemiologic relevance. Thus, this review may provide foundations for the potential use of bovine Lf alone or as a natural adjunct agent to increase the effectiveness and reduce the side effects of anticancer chemotherapy.

Exploring the room for repurposed hydroxychloroquine to impede COVID-19: toxicities and multipronged combination approaches with pharmaceutical insights

Introduction: SARS-CoV-2 has fatally affected the whole world with millions of deaths. Amidst the dilemma of a breakthrough in vaccine development, hydroxychloroquine (HCQ) was looked upon as a prospective repurposed candidate. It has confronted numerous controversies in the past few months as a chemoprophylactic and treatment option for COVID-19. Recently, it has been withdrawn by the World Health Organization for its use in an ongoing pandemic. However, its benefit/risk ratio regarding its use in COVID-19 disease remains poorly justified. An extensive literature search was done using Scopus, PubMed, Google Scholar, www.cdc.gov, www.fda.gov, and who.int.Areas covered: Toxicity vexations of HCQ; pharmaceutical perspectives on new advances in drug delivery approaches; computational modeling (PBPK and PD modeling) overtures; multipronged combination approaches for enhanced synergism with antiviral and anti-inflammatory agents; immuno-boosting effects.Expert commentary: Harnessing the multipronged pharmaceutical perspectives will optimistically help the researchers, scientists, biotech, and pharmaceutical companies to bring new horizons in the safe and efficacious utilization of HCQ alone or in combination with remdesivir and immunomodulatory molecules like bovine lactoferrin in a fight against COVID-19. Combinational therapies with free forms or nanomedicine based targeted approaches can act synergistically to boost host immunity and stop SARS-CoV-2 replication and invasion to impede the infection.

Ameliorative effects of colostrum against DMBA hepatotoxicity in rats

Colostrum, the sole diet for newborns, is an emerging nutraceutical. To date, the chemopreventive effect of Bovine Colostrum against liver injury induced by the potent carcinogen, 7,12-dimethyl-Benz[a]anthracene (DMBA) is unexplored. Humans are daily exposed to DMBA which is a highly lipophilic environmental organic pollutant. The study aimed to investigate the hepatoprotective role of Bovine Colostrum against DMBA-induced hepatotoxicity using a rat model. Fifty male rats were divided into five groups; GI (control), GII (olive oil, vehicle for DMBA), GIII (DMBA), GIV (DMBA + Bovine Colostrum), GV (Bovine Colostrum). After 12 weeks, body weight changes and mortality were calculated. Histological and ultrastructural examinations of liver tissue were performed. Expressions of p53, TGFβ2, TNF-α, S6K2, and c20orf20 were assessed by RT-PCR. Post-treatment with Bovine Colostrum increased both the body weight and the survival rate of rats treated with DMBA. In addition, remarkable protection against the pathological effect of DMBA was noted. Ultrastructurally, Bovine Colostrum ameliorated/prevented most of the toxic effects of DMBA on hepatocytes, including irregularities of nuclear envelope, clumping, and margination of heterochromatin aggregates, segregated nucleoli, and mitochondrial pleomorphism. Bovine Colostrum administration down-regulated p53, C20orf20, and S6K2 mRNA levels, and up-regulated TNF-α and TGFβ2. In conclusion, Bovine Colostrum have a protective effect against DMBA-induced toxicity on the liver of albino rats. Consequently, Bovine Colostrum may prevent polycyclic aromatic hydrocarbons-induced hepatotoxicity and may be useful in promoting human health if supplemented in the diet.

Evaluation of Milk Colostrum Derived Lactoferrin of Sahiwal (Bos indicus) and Karan Fries (Cross-Bred) Cows for Its Anti-Cancerous Potential

Lactoferrin (Lf) is an iron-binding glycoprotein protein known to have immune-modulatory role and recently, its anticancerous effect against different cancer cell types was emphasized. In the present investigation, a comparative evaluation of anticancer potential of colostrum-derived lactoferrin from Indian native zebu cow (Sahiwal, SAC), crossbred (Karan Fries, KFC) and commercially available (C-Lf) lactoferrin from exotic cow using cellular models was made. A protocol was standardized successfully to purify Lf protein from colostrum of both breeds using HPLC and purity was confirmed by LC-MS. A standardized dose of 750 µg/mL Lf was used to treat two cell types MDA-MB-231 and MCF-7 with Lf from three different sources; SAC-Lf, KFC-Lf and C-Lf for 48 h and 72 h. Different cellular parameters including cytotoxicity, viability, apoptosis and cell proliferation were determined. Comparatively, Lf from commercial source (C-Lf) had maximum effect in both cell types followed by SAC-Lf and KFC-Lf. Further, transcriptional changes in genes associated with apoptosis (Bax and Bcl-2), tumor progression (p53, p21, CD44 and NF-κβ) and survival (survivin) were evaluated in Lf treatment. The overall results strongly emphasized to the fact that Lf purified from cow colostrum has the capacity to inhibit the in vitro growth of cancerous cell lines albeit to a varied extent.

The effects of colostrum on some biochemical parameters in the experimental intoxication of rats with paracetamol

In the current study, the possible prophylactic and therapeutic effects of colostrum (COL) on acute organ injury caused by paracetamol (PAR) in rats were evaluated. Within the scope of this study, a 2-month-old male (150-200 g) 70 Wistar Albino rat was used and a total of seven groups were designed. The first group (CNT) was maintained for control purposes. The second group (COL-1) was given COL for 1 day, at a dose of 500 mg/kg at 6-h intervals, and blood and tissue sampling was performed at 24 h. The third group (COL-7) received COL for 7 days, at a dose of 500 mg/kg at 6-h intervals on day 1 and at a daily dose of 500 mg/kg on the following days, and blood and tissue samples were taken at the end of seventh day. The fourth group (PAR-1) was administered with PAR at a dose of 1.0 g/kg bw and was blood and tissue sampled at 24 h. The fifth group (PAR-7) received PAR at a dose of 1.0 g/kg bw on day 1 and was blood and tissue was removed at the end of day 7. The sixth group (PAR+COL-1) was administered with a combination of PAR (1 g/kg bw) and COL (500 mg/kg at 6-h intervals), and blood and tissue samples were collected at 24 h. The seventh group (PAR+COL-7) received 1.0 g/kg bw of PAR on day 1 and was given COL throughout the 7-day study period (at a dose of 500 mg/kg at 6-h intervals on day 1 and at a daily dose of 500 mg/kg on the following days). In the seventh group, blood and tissue samples were taken at the end of seventh day. Alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), glucose, creatinine, triglyceride, total bilirubin, total protein and albumin levels/activities were analysed in the serum samples. The malondialdehyde (MDA), nitric oxide (NO), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) levels/activities, known as oxidative stress parameters, were assayed for tissue homogenates and blood (erythrocytes/plasma); in addition, enzyme activities of GSH S-transferase (GST), cytochrome P4502E1 (CYP2E1), NADH-cytochrome b5 reductase (CYTB5), glucose-6-phosphate dehydrogenase (G6PD), NADPH-cytochrome P450 C reductase (CYTC) and glutathione (GSH) levels/activities defined as drug metabolising parameters were measured in liver homogenates. In result, it was determined that PAR caused significant alterations in some biochemical and lipid peroxidation parameters and the activities/levels of drug metabolising parameters in the liver and that COL normalised some of these parameters and reduced PAR-induced tissue damage.

Molecular mechanism of inhibitory effects of bovine lactoferrin on the growth of oral squamous cell carcinoma

Background

Lactoferrin (LF), a member of the transferrin family, recently has been demonstrated to have anticancer effects on various cancers including oral squamous cell carcinoma (OSCC). However, little is known about the underlying mechanisms of its effects on OSCC. Therefore, we aimed to investigate the mechanism of the suppressive effects of bovine LF (bLF) on the growth of OSCC cells.

Methods

In the current study, HSC2, HSC3, HSC4 and normal human oral keratinocytes (RT7) cell lines were tested with bLF 1, 10, and 100 μg/ml. The effects and detail mechanisms of bLF on proliferation and apoptosis of cells were investigated using flow cytometry and western blotting.

Results

We found that bLF (1, 10, and 100 μg/ml) induced activation of p53, a tumor suppressor gene, is associated with the induction of cell cycle arrest in G1/S phase and apoptosis in OSCC. Moreover, bLF downregulated the phosphorylation of Akt and activated suppressor of cytokine signaling 3 (SOCS3), thereby attenuating multiple signaling pathways including mTOR/S6K and JAK/STAT3. Interestingly, we revealed that bLF exerted its effect selectively against HSC3 but not on RT7 via different effects on the phosphorylation status of NF-κB and Akt.

Conclusion

This is the first report showing that bLF selectively suppresses proliferation through mTOR/S6K and JAK/STAT3 pathways and induction of apoptosis in OSCC. This study provides important new findings, which might be useful in the prevention and treatment of OSCC.

Doxorubicin Conjugated to Immunomodulatory Anticancer Lactoferrin Displays Improved Cytotoxicity Overcoming Prostate Cancer Chemo resistance and Inhibits Tumour Development in TRAMP Mice

Advanced, metastatic, castration resistant and chemo-resistant prostate cancer has triggered change in the drug development landscape against prostate cancer. Bovine lactoferrin (bLf) is currently attracting attention in clinics for its anti-cancer properties and proven safety profile. bLf internalises into cancer cells via receptor mediated endocytosis, boosts immunity and complements chemotherapy. We employed bLf as an excellent functional carrier protein for delivering doxorubicin (Dox) into DU145 cells, CD44+/EpCAM+ double positive enriched DU145 3D prostaspheres and drug resistant ADR1000-DU145 cells, thus circumventing Dox efflux, to overcome chemo-resistance. Successful bLf-Dox conjugation with iron free or iron saturated bLf forms did not affect the integrity and functionality of bLf and Dox. bLf-Dox internalised into DU145 cells within 6 h, enhanced nuclear Dox retention up to 24 h, and proved significantly effective (p < 0.001) in reducing LC₅₀ value of Dox from 5.3 μM to 1.3 μM (4 fold). Orally fed iron saturated bLf-Dox inhibited tumour development, prolonged survival, reduced Dox induced general toxicity, cardiotoxicity, neurotoxicity in TRAMP mice and upregulated serum levels of anti-cancer molecules TNF-α, IFN-γ, CCL4 and CCL17. The study identifies promising potential of a novel and safer bLf-Dox conjugate containing a conventional cytotoxic drug along with bLf protein to target drug resistance.

Biodegradable Eri silk nanoparticles as a delivery vehicle for bovine lactoferrin against MDA-MB-231 and MCF-7 breast cancer cells

This study used the Eri silk nanoparticles (NPs) for delivering apo-bovine lactoferrin (Apo-bLf) (~2% iron saturated) and Fe-bLf (100% iron saturated) in MDA-MB-231 and MCF-7 breast cancer cell lines. Apo-bLf and Fe-bLf-loaded Eri silk NPs with sizes between 200 and 300 nm (±10 nm) showed a significant internalization within 4 hours in MDA-MB-231 cells when compared to MCF-7 cells. The ex vivo loop assay with chitosan-coated Fe-bLf-loaded silk NPs was able to substantiate its future use in oral administration and showed the maximum absorption within 24 hours by ileum. Both Apo-bLf and Fe-bLf induced increase in expression of low-density lipoprotein receptor-related protein 1 and lactoferrin receptor in epidermal growth factor (EGFR)-positive MDA-MB-231 cells, while transferrin receptor (TfR) and TfR2 in MCF-7 cells facilitated the receptor-mediated endocytosis of NPs. Controlled and sustained release of both bLf from silk NPs was shown to induce more cancer-specific cytotoxicity in MDA-MB-231 and MCF-7 cells compared to normal MCF-10A cells. Due to higher degree of internalization, the extent of cytotoxicity and apoptosis was significantly higher in MDA-MB-231 (EGFR+) cells when compared to MCF-7 (EGFR−) cells. The expression of a prominent anticancer target, survivin, was found to be downregulated at both gene and protein levels. Taken together, all the observations suggest the potential use of Eri silk NPs as a delivery vehicle for an anti-cancer milk protein, and indicate bLf for the treatment of breast cancer.

Upregulation of sodium iodide symporter (NIS) protein expression by an innate immunity component: Promising potential for targeting radiosensitive retinoblastoma

Retinoblastoma (RB), a malignant tumour of the eye arising from developing retina, is the most frequent primary intraocular malignancy of childhood. Its primary management with chemotherapy involves combination regimen of etoposide, vincristine and carboplatin and intra vitreal chemotherapy using melphalan when vitreous seeds develop. Radiotherapy is another effective mode in treating RB. We recently explored the notion if radiotherapy in RB can be mediated via Sodium Iodide Symporter (NIS), an intrinsic membrane glycoprotein which is a key regulator of iodide access to thyroid gland. Its expression has been exploited successfully for diagnostic imaging and molecular radionuclide-based therapy of thyroid cancer. We determined that NIS is expressed endogenously in RB tumour tissues, and in retinoblastoma cell lines Y79 and Weri-Rb-1, and therefore made an attempt to enhance the endogenously low expression of NIS protein in both Y79 and Weri-Rb-1 cells. Here we report about the potential of bovine lactoferrin (bLf) which is a known chemo preventive and emerging safe anti-cancer bio drug, as well as a natural transcriptional activator of genes, to enhance the endogenous expression of NIS in Y79 and Weri-Rb-1 cells. Real time PCR revealed that both cell lines express mRNA of lactoferrin receptors while flow cytometry and confocal microscopy showed the cells efficiently internalize bLf which upregulates NIS expression. These findings highlight an important step that could be taken towards the development of less harmful approaches for the treatment of RB by employing natural supplement bLf (with its clinically proven safe profile), and warrants further studies in future, focussing on enhancing NIS expression in RB cells and NIS functional assays in these cells.

Cissus quadrangularis inhibits IL-1β induced inflammatory responses on chondrocytes and alleviates bone deterioration in osteotomized rats via p38 MAPK signaling

INTRODUCTION

Inflammatory mediators are key players in the pathogenesis of osteoarthritis (OA) and bone destruction. Conventional drugs suppress symptomatic activity and have no therapeutic influence on disease. Cissus quadrangularis and Withania somnifera are widely used for the treatment of bone fractures and wounds; however, the cellular and molecular mechanisms regulated by these herbals are still unclear.

METHODS

We established an in vitro OA culture model by exposing human chondrocytes to proinflammatory cytokine and interleukin (IL)-1β for 36 hours prior to treatment with the herbals: C. quadrangularis, W. somnifera, and the combination of the two herbals. Cell viability, toxicity, and gene expression of OA modifying agents were examined. In addition, expression of survivin, which is crucial for cell growth, was analyzed. In vivo work on osteotomized rats studied the bone and cartilage regenerative effects of C. quadrangularis, W. somnifera, and the combination therapy.

RESULTS

Exposure of chondrocytes to IL-1β induced significant toxicity and cell death. However, herbal treatment alleviated IL-1β induced cell toxicity and upregulated cell growth and proliferation. C. quadrangularis inhibited gene expression of cytokines and matrix metalloproteinases, known to aggravate cartilage and bone destruction, and augmented expression of survivin by inhibiting p38 MAPK. Interestingly, osteotomized rats treated with C. quadrangularis drastically enhanced alkaline phosphatase and cartilage tissue formation as compared to untreated, W. somnifera only, or the combination of both herbals.

CONCLUSION

Our findings demonstrate for the first time the signaling mechanisms regulated by C. quadrangularis and W. somnifera in OA and osteogenesis. We suggest that the chondroprotective effects and regenerative ability of these herbals are via the upregulation of survivin that exerts inhibitory effects on the p38 MAPK signaling pathway. These findings thus validate C. quadrangularis as a potential therapeutic for rheumatic disorders.

Iron-free and iron-saturated bovine lactoferrin inhibit survivin expression and differentially modulate apoptosis in breast cancer

BACKGROUND

Iron binding, naturally occurring protein bovine lactoferrin (bLf) has attracted attention as a safe anti-cancer agent capable of inducing apoptosis. Naturally, bLf exists partially saturated (15-20%) with Fe(3+) however, it has been demonstrated that manipulating the saturation state can enhance bLf's anti-cancer activities.

METHODS

Apo-bLf (Fe(3+) free) and Fe-bLf (>90% Fe(3+) Saturated) were therefore, tested in MDA-MB-231 and MCF-7 human breast cancer cells in terms of cytotoxicity, proliferation, migration and invasion. Annexin-V Fluos staining was also employed in addition to apoptotic protein arrays and Western blotting to determine the specific mechanism of bLf-induced apoptosis with a key focus on p53 and inhibitor of apoptosis proteins (IAP), specifically survivin.

RESULTS

Apo-bLf induced significantly greater cytotoxicity and reduction in cell proliferation in both cancer cells showing a time and dose dependent effect. Importantly, no cytotoxicity was detected in normal MCF-10-2A cells. Both forms of bLf significantly reduced cell invasion in cancer cells. Key apoptotic molecules including p53, Bcl-2 family proteins, IAP members and their inhibitors were significantly modulated by both forms of bLf, though differentially in each cell line. Most interestingly, both Apo-bLf and Fe-bLf completely inhibited the expression of survivin protein (key IAP), after 48 h at 30 and 40 nM in cancer cells.

CONCLUSIONS

The capacity of these forms of bLf to target survivin expression and modulation of apoptosis demonstrates an exciting potential for bLf as an anti-cancer therapeutic in the existing void of survivin inhibitors, with a lack of successful inhibitors in the clinical management of cancer.

Matrix-immobilized yeast for large-scale production of recombinant human lactoferrin

An improved method of recombinant human lactoferrin (hLF) expression in rich culture medium is demonstrated using macroporous microencapsulation.

Nanocapsules loaded with iron-saturated bovine lactoferrin have antimicrobial therapeutic potential and maintain calcium, zinc and iron metabolism

AIM

This study aimed to evaluate the potential antimicrobial efficacy of alginate gel-encapsulated ceramic nanocarriers loaded with iron-saturated bovine lactoferrin (Fe-bLf) nanocarriers/nanocapsules (AEC-CP-Fe-bLf NCs).

MATERIALS & METHODS

The antimicrobial activities of non-nanoformulated apo (iron free), Fe-bLf and native forms of Australian bLf against pathogenic Salmonella typhimurium (wild strain) were studied in vitro. The efficacy of AEC-CP-Fe-bLf NCs were checked in vivo using Balb/c mice model.

RESULTS

The study revealed that native bLf is more effective in combating infection than the conventional drug ciprofloxacin (0.4 mg/ml). The efficacy of the drug was also revealed in vivo when BALB/c mice that, after being challenged with S. typhimurium (200 μl of 10(8) CFU/ml suspension), were fed orally with a nanoformulated bLf diet and the infection was observed to be eliminated. However, chronic infection developed in the group of infected mice that did not receive any drug treatment, as well as the mice treated with ciprofloxacin. The immune response to bacterial infection and to various drug treatments thereafter was studied in the mice.

CONCLUSION

The study concludes that bLf and nanoformulated Fe-bLf are more effective in the treatment of Salmonella-infected mice than ciprofloxacin.