Whey Protein Concentrate WPC-80 Improves Antioxidant Defense Systems in the Salivary Glands of 14-Month Wistar Rats

Bioactive milk peptides: an updated comprehensive overview and database

Partial digestion of milk proteins leads to the formation of numerous bioactive peptides. Previously, our research team thoroughly examined the decades of existing literature on milk bioactive peptides across species to construct the milk bioactive peptide database (MBPDB). Herein, we provide a comprehensive update to the data within the MBPDB and a review of the current state of research for each functional category from in vitro to animal and clinical studies, including angiotensin-converting enzyme (ACE)-inhibitory, antimicrobial, antioxidant, dipeptidyl peptidase (DPP)-IV inhibitory, opioid, anti-inflammatory, immunomodulatory, calcium absorption and bone health and anticancer activity. This information will help drive future research on the bioactivities of milk peptides.

Mitochondrial Glutathione in Cellular Redox Homeostasis and Disease Manifestation

Mitochondria are critical for providing energy to maintain cell viability. Oxidative phosphorylation involves the transfer of electrons from energy substrates to oxygen to produce adenosine triphosphate. Mitochondria also regulate cell proliferation, metastasis, and deterioration. The flow of electrons in the mitochondrial respiratory chain generates reactive oxygen species (ROS), which are harmful to cells at high levels. Oxidative stress caused by ROS accumulation has been associated with an increased risk of cancer, and cardiovascular and liver diseases. Glutathione (GSH) is an abundant cellular antioxidant that is primarily synthesized in the cytoplasm and delivered to the mitochondria. Mitochondrial glutathione (mGSH) metabolizes hydrogen peroxide within the mitochondria. A long-term imbalance in the ratio of mitochondrial ROS to mGSH can cause cell dysfunction, apoptosis, necroptosis, and ferroptosis, which may lead to disease. This study aimed to review the physiological functions, anabolism, variations in organ tissue accumulation, and delivery of GSH to the mitochondria and the relationships between mGSH levels, the GSH/GSH disulfide (GSSG) ratio, programmed cell death, and ferroptosis. We also discuss diseases caused by mGSH deficiency and related therapeutics.

Radioprotective potential of whey protein against gamma irradiation-induced lingual damage

Introduction: Ionizing radiation (IR) is effectively used in the treatment of oral malignancies; however, it might also significantly harm the surrounding tissues. Whey protein isolate (WP) is a protein derived from milk that exhibits a wide range of bioactivities. Therefore, the present research aimed to delineate the mitigating impact of WP against gamma irradiation-induced lingual damage. Methods: Rats were randomized into 5 groups: Control (saline, orally, 14 days), WP (WP; 0.5 g/kg b. w., orally, 14 days), IR (saline, orally, 14 days, exposed to 6 and 3 Gy on days 4 and 6, respectively), WP+IR (WP was given orally for 14 days before and after IR exposure; exposed to 6 and 3 Gy on days 4 and 6, respectively), and IR+WP (WP, orally, started 24 h after 1st IR exposure till the end of the experiment) groups. Samples were collected at two-time intervals (on the 7th and 14th days). Results and Discussion: Oxidative stress was stimulated upon IR exposure in tongue, indicated by boosted malondialdehyde (MDA) level, along with a decrease in the total antioxidant capacity (TAC) level, superoxide dismutase (SOD), and catalase (CAT) activities. Additionally, IR exposure depicted an increase of serum IgE, inflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin (IL)-6, along with overexpression mRNA levels of nuclear factor kappa-B transcription factor/p65 (NF-κB/p65), and down-regulation of nuclear factor erythroid 2-related factor 2 (NRF2) and heme oxygenase (HO-1) mRNA levels in tongue tissue. Moreover, IR triggered alterations in lingual histological architecture. The antioxidant and anti-inflammatory properties of WP mitigated oxidative damage, inflammation, and desquamation that were brought on following IR exposure. The protective administration of WP markedly decreases IR-induced lingual harm compared to the mitigation protocol. Our findings recommend WP supplements to the diets of cancer patients undergoing IR that might aid radioprotective effects.

Glutathione system enhancement for cardiac protection: pharmacological options against oxidative stress and ferroptosis

The glutathione (GSH) system is considered to be one of the most powerful endogenous antioxidant systems in the cardiovascular system due to its key contribution to detoxifying xenobiotics and scavenging overreactive oxygen species (ROS). Numerous investigations have suggested that disruption of the GSH system is a critical element in the pathogenesis of myocardial injury. Meanwhile, a newly proposed type of cell death, ferroptosis, has been demonstrated to be closely related to the GSH system, which affects the process and outcome of myocardial injury. Moreover, in facing various pathological challenges, the mammalian heart, which possesses high levels of mitochondria and weak antioxidant capacity, is susceptible to oxidant production and oxidative damage. Therefore, targeted enhancement of the GSH system along with prevention of ferroptosis in the myocardium is a promising therapeutic strategy. In this review, we first systematically describe the physiological functions and anabolism of the GSH system, as well as its effects on cardiac injury. Then, we discuss the relationship between the GSH system and ferroptosis in myocardial injury. Moreover, a comprehensive summary of the activation strategies of the GSH system is presented, where we mainly identify several promising herbal monomers, which may provide valuable guidelines for the exploration of new therapeutic approaches.

Whey protein concentrate protects against age-dependent alteration in redox biomarkers

Aging is associated with decreased cellular cysteine uptake, which acts as a precursor for glutathione biosynthesis. Whey protein, a liquid aspect of milk, is an effective cysteine delivery system. The study was undertaken to evaluate the potential role of whey protein concentrate (WPC) on the redox biomarkers during aging. Male Wistar rats were divided into following four groups: young control (4 months old); young treated with WPC (300 mg/kg b.w./day orally); old (24 months old) control; old treated with WPC for 28 days. After treatment, changes in body weight, lipid profile and levels of redox biomarkers were determined. A marked decrease in prooxidants such as reactive oxygen species, lipid peroxidation and protein carbonyl and significant (p ≤ 0.05) increase in antioxidants such as reduced glutathione and GST levels were observed after WPC supplementation in old age rats. We also found marked decrease in the level of sialic acid and AGEs after WPC supplementation. In conclusion, WPC provides protection against age-dependent redox imbalance which might be attributed to its antioxidant activity.

The Influence of Dietary Fibers on Physicochemical Properties of Acid Casein Processed Cheese Sauces Obtained with Whey Proteins and Coconut Oil or Anhydrous Milk Fat

This study aimed to evaluate different fibers (acacia, bamboo, citrus or potato) on texture, rheological properties, color, density, and water activity of processed cheese sauces (PCS) based on acid casein, WPC80 and anhydrous milk fat or organic coconut oil. The interaction between the type of oil/fat, the fiber type and the fiber content was significant regarding almost all parameters studied. The computer vision system (CVS) showed that color changes of sauces could be noticeable by consumers. The main factor influencing the change in all products’ hardness was not fat/oil, but added fibers and their concentrations. The highest increase in hardness, adhesiveness and viscosity was observed in products with potato fiber. The value of storage modulus (G′) was higher than the loss modulus (G″) and tan (δ) < 1 for all samples. Different fibers and their amounts did not influence the water activity of cheese sauces obtained with organic coconut oil (OCO) or anhydrous milk fat (AMF).

Electrospinning Proteins for Wound Healing Purposes: Opportunities and Challenges

With the growth of the aging population worldwide, chronic wounds represent an increasing burden to healthcare systems. Wound healing is complex and not only affected by the patient's physiological conditions, but also by bacterial infections and inflammation, which delay wound closure and re-epithelialization. In recent years, there has been a growing interest for electrospun polymeric wound dressings with fiber diameters in the nano- and micrometer range. Such wound dressings display a number of properties, which support and accelerate wound healing. For instance, they provide physical and mechanical protection, exhibit a high surface area, allow gas exchange, are cytocompatible and biodegradable, resemble the structure of the native extracellular matrix, and deliver antibacterial agents locally into the wound. This review paper gives an overview on cytocompatible and biodegradable fibrous wound dressings obtained by electrospinning proteins and peptides of animal and plant origin in recent years. Focus is placed on the requirements for the fabrication of such drug delivery systems by electrospinning as well as their wound healing properties and therapeutic potential. Moreover, the incorporation of antimicrobial agents into the fibers or their attachment onto the fiber surface as well as their antimicrobial activity are discussed.

The Relationship between Suicide and Oxidative Stress in a Group of Psychiatric Inpatients

Diagnosis of suicide risk is a clinical challenge requiring an interdisciplinary therapeutic approach. Except for psychological explanation of the suicidal mechanism, there is evidence that it is associated with brain chemistry disturbances as oxidative stress. The objective of this study was to explore the role of oxidative stress components in suicidality comparing subjects at different stages of suicide. The study included psychiatric inpatients aged 18–64 (n = 48) with different psychiatric diagnoses. Blood specimens were collected from subjects and tested for oxidative stress biomarkers: superoxide dismutase (SOD), dityrozine (DT), oxidative stress index (OSI), glutathione peroxidase (GPx), total antioxidant capacity (TAC trolox), ferric reducing ability of plasma (FRAP), total oxidant status (TOS), catalase (CAT), advanced glycoxidation end products (AGE), NADPH oxidase (NOX), and advanced oxidation protein products (AOPP). The Columbia Severity Suicide Scale (C-SSRS) was used for suicidality assessment. Subjects with a history of suicide ideations over the last three months had significantly higher levels of NOX, AOPP, and OSI. There was no significant relationship to any oxidative stress component levels either with a history of suicide behaviors or with suicide attempts over the last three months. The levels of NOX and AOPP were both positively correlated to the intensity of suicidal thoughts. Moreover, there was a positive correlation between a number of suicide attempts during a lifetime with AGE and DT and negative with CAT. Similarly, the subjects with a history of suicide attempts had significantly higher AGE and DT levels and lower CAT values. The study confirmed that oxidative stress plays an important role in the pathophysiology of suicide and specific oxidative stress measures vary in suicidal and non-suicidal psychiatric inpatients.

Evaluation of whey protein sources on performance, liver antioxidants and immune responses of broiler chickens challenged with ethanol

To evaluate the effects of whey protein (WP) sources on performance, liver antioxidants and immune responses of broiler chickens, 300 one-d-old male Ross 308 chickens were randomly allocated into six treatments with five replications of 10 birds each. This study was conducted on the basis of a completely randomized design in a 3 × 2 factorial arrangement with dietary supplemental WP sources (no WP; 2% WP and 2% whey protein concentrate (WPC)) and ethanol (zero and 6%) into drinking water. Birds were challenged with ethanol 6% from 10 to 24 days of age. Growth performance, immune responses, intestinal morphology and antioxidant enzymes were assessed in both challenged and non-challenged groups. There was a significant interaction between ethanol and WP sources for growth performance, so that weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) were significantly improved in broiler chickens challenged with ethanol and fed with WP (p < .05). Intestinal morphology, humoral responses and heterophil to lymphocyte ratio (H/L) were not affected by WP sources. Cellular immunity responses were significantly lower in control group and challenged birds fed with WP compared with other groups after 48 hr of phytohemagglutinin-P (PHA-P) injection. Ethanol challenge decreased liver antioxidant enzyme activities and increased levels of malondialdehyde (MDA) and alanine aminotransferase (ALT) activities. Dietary inclusion of WP and WPC increased levels of liver antioxidant enzymes and decreased MDA and ALT activities. It can be recommended to use WP for improving the growth performance and liver antioxidant enzymes in broiler chickens challenged with ethanol.

Oxidative Stress and Inflammation Interdependence in Multiple Sclerosis

The study aims to explore the oxidative status related to inflammation in peripheral blood of stable relapsing-remitting multiple sclerosis (MS) patients with low disability. In this study, 31 people were included and divided into two groups: an MS group in which 16 relapsing-remitting MS patients with a low disability level (age 38.9 ± 7.08, EDSS median 2.5) were included and a control group that contains 15 healthy volunteers of similar age to the MS group. Thiobarbituric acid reactive substances (TBARS), protein carbonyl level (PCO), total antioxidant capacity (TAC) as oxidative stress markers, neutrophil/lymphocyte ratio (NLR), and erythrocyte sedimentation rate (ESR) were analyzed in the peripheral blood sample of the healthy and the MS patients to establish the oxidative stress/inflammatory level using conventional plasma markers. In this study, we showed that the pro-inflammatory status of the relapse-remitting stage of diseases can be easily and accurately appreciated by NLR. An increased NLR is associated with a decreased antioxidant capacity, even in the early stage of neuronal damage. Oxidative stress associated with inflammation aggravates the functional outcome, potentiates neuronal damage, and can accelerate the progression of the disease.

Whey proteins: targets of oxidation, or mediators of redox protection

Bovine whey proteins are highly valued dairy ingredients. This is primarily due to their amino acid content, digestibility, bioactivities and their processing characteristics. One of the reported bioactivities of whey proteins is antioxidant activity. Numerous dietary intervention trials with humans and animals indicate that consumption of whey products can modulate redox biomarkers to reduce oxidative stress. This bioactivity has in part been assigned to whey peptides using a range of biochemical or cellular assays in vitro. Superimposing whey peptide sequences from gastrointestinal samples, with whey peptides proven to be antioxidant in vitro, allows us to propose peptides from whey likely to exhibit antioxidant activity in the diet. However, whey proteins themselves are targets of oxidation during processing particularly when exposed to high thermal loads and/or extensive processing (e.g. infant formula manufacture). Oxidative damage of whey proteins can be selective with regard to the residues that are modified and are associated with the degree of protein unfolding, with α-Lactalbumin more susceptible than β-Lactoglobulin. Such oxidative damage may have adverse effects on human health. This review summarises how whey proteins can modulate cellular redox pathways and conversely how whey proteins can be oxidised during processing. Given the extensive processing steps that whey proteins are often subjected to, we conclude that oxidation during processing is likely to compromise the positive health attributes associated with whey proteins.

Antihepatocarcinogenic activity of whey protein concentrate and lactoferrin in diethylnitrosamine-treated male albino mice

Hepatocellular carcinoma is considered one of the most prevalent and lethal malignancies worldwide. Chemotherapy with cytotoxic agents showed a low response rate with possible toxic effects. Recently, some emphases have been placed on the anticancer properties of bovine whey protein and its components, especially lactoferrin. The present study aimed to evaluate and compare the antihepatocarcinogenic activity of bovine whey protein concentrate (WPC, 300 and 600 mg/kg body weight) and lactoferrin (30 and 60 mg/kg body weight), orally and daily for 14 weeks, in the mice model of diethylnitrosamine (DEN)-induced hepatocarcinogenesis. The results showed that both WPC and lactoferrin (in a dose-dependent manner) alleviated significantly (P < .001) the elevation in serum markers of liver carcinoma and inflammation in the DEN-treated mice. Also, they exhibited a great amelioration in the livers' histological structure of the DEN-treated mice by 37.0% to 66.7%. In addition, they decreased significantly (P < .001) the hepatic DNA fragmentation in the DEN-treated mice by 23.1% to 32.7%. Only, the high doses of WPC and lactoferrin completely modulated the decrease in the activity of liver enzymic antioxidant defense system (catalase, glutathione peroxidase, and superoxide dismutase) and improved significantly (P < .01-.001) the concentration of hepatic reduced glutathione of the DEN-treated mice. Moreover, the high doses of WPC and lactoferrin reduced significantly (P < .05-.001) the elevation in the concentrations of hepatic active caspases 3, 8, and 9 of the DEN-treated mice. In conclusion, both WPC and lactoferrin were effective in inhibiting the hepatocarcinogenic activity of DEN in mice model through their ability to alleviate the hepatic inflammation and apoptosis.

High Protein Diet Induces Oxidative Stress in Rat Cerebral Cortex and Hypothalamus

This is the first study to analyze the impact of high protein diet (HPD) on antioxidant defense, redox status, as well as oxidative damage on both a local and systemic level. Male Wistar rats were divided into two equal groups (n = 9): HPD (44% protein) and standard diet (CON; 24.2% protein). After eight weeks, glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase-1 (SOD-1), reduced glutathione (GSH), uric acid (UA), total antioxidant (TAC)/oxidant status (TOS) as well as advanced glycation end products (AGE), 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA) were analyzed in the serum/plasma, cerebral cortex, and hypothalamus of HPD and CON rats. HPD resulted in higher UA concentration and activity of GPx and CAT in the hypothalamus, whereas in the cerebral cortex these parameters remained unchanged. A significantly lower GSH content was demonstrated in the plasma and hypothalamus of HPD rats when compared to CON rats. Both brain structures expressed higher content of 4-HNE and MDA, whereas AGE was increased only in the hypothalamus of HPD animals. Despite the enhancement in antioxidant defense in the hypothalamus, this mechanism does not protect the hypothalamus from oxidative damage in rats. Hypothalamus is more susceptible to oxidative stress caused by HPD.

Whey Protein Concentrate WPC-80 Intensifies Glycoconjugate Catabolism and Induces Oxidative Stress in the Liver of Rats

The aim of this study was to evaluate the effect of whey protein concentrate (WPC-80) on glycoconjugate catabolism, selected markers of oxidative stress and liver inflammation. The experiment was conducted on male Wistar rats (n = 63). The animals from the study group were administered WPC-80 at a dose of 0.3 or 0.5 g/kg body weight for 7, 14 or 21 days, while rats from the control group received only 0.9% NaCl. In liver homogenates, we assayed the activity of N-acetyl-β-D-hexosaminidase (HEX), β-glucuronidase (GLU), β-galactosidase (GAL), α-mannosidase (MAN), α-fucosidase (FUC), as well as the level of reduced glutathione (GSH), malondialdehyde (MDA), interleukin-1β (IL-1β) and transforming growth factor-β1 (TGF-β1). A significantly higher activity of HEX, GLU, MAN and FUC were found in the livers of rats receiving WPC-80 compared to controls. Serum ALT and AST were significantly higher in the animals supplemented with WPC-80 at a dose of 0.5 g/kg body weight for 21 days. In the same group of animals, enhanced level of GSH, MDA, IL-1β and TGF-β1 were also observed. WPC-80 is responsible for intensive remodelling of liver tissue and induction of oxidative stress especially at a dose of 0.5 g/kg body weight.

Salivary Biomarkers of Oxidative Stress in Children with Chronic Kidney Disease

There are still missing non-invasive biomarkers of chronic kidney disease (CKD) in children. Therefore, the aim of the study was to evaluate oxidative stress indicators in the non-stimulated (NWS) and stimulated saliva (SWS) of CKD children (n = 25) and healthy controls (n = 25). Salivary antioxidants (catalase (CAT), peroxidase (Px), superoxide dismutase (SOD), uric acid (UA), reduced glutathione (GSH), albumin), redox status (total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI)), and oxidative damage products (advanced glycation end products (AGE), advanced oxidation protein products (AOPP), malondialdehyde (MDA)) were evaluated. We have demonstrated the significantly higher activity of SWS GPx and SOD, as well as elevated concentrations of UA and albumin in NWS and SWS of CKD children vs. the control group. TAC, TOS and OSI were significantly higher only in SWS, while oxidative damage products (AGE, AOPP and MDA) were significantly higher in both NWS and SWS of CKD children. ROC analysis showed a considerably high diagnostic value of AOPP in both NWS and SWS of CKD children compared to controls (AUC = 0.92; 0.98). CKD is responsible for disturbances in salivary antioxidant systems and oxidative damage to proteins and lipids. Salivary AOPP can be a potential biomarker of CKD in children.