Novel chemiluminescence-inducing cocktails, part I: The role in light emission of combinations of luminal with SIN-1, selenite, albumin, glucose oxidase and Co2+

Direct effects of phenolic compounds on the mammary gland: In vivo and ex vivo evidence

We assessed the potential of Pistacia lentiscus (lentisk) phenolic compounds to enhance production of milk composition in lactating goats and caprine primary mammary epithelial cells (MEC). Damascus goats were given a lentisk infusion (LI) or fresh water (FW) to drink, in a crossover design. Milk from LI vs. FW goats was 0.43% richer in fat and 30% in omega 3 fatty acids. Lentisk infusion enhanced antioxidant capacity of plasma and milk by 37% and 30% respectively, and induced transcriptional activation of antioxidant genes. To assess the direct effect of polyphenols on milk quality in terms of composition and antioxidant capacity, we used plasma collected from goats fed hay (HP) or browsed on phenolic compounds-rich pasture (primarily lentisk; PP) as a conditioning medium for primary culture of MEC. PP increased 2-fold cellular triglyceride content and 2.4-fold intracellular casein, and increased ATP production and non-mitochondrial oxygen consumption. Taken together, the results imply that lentisk phenolic compounds affect blood, MEC and milk oxidative status, which increase fat production by the mammary gland.

Dietary pomegranate peel improves milk quality of lactating ewes: Emphasis on milk fat globule membrane properties and antioxidative traits

Concentrated pomegranate peel extract (CPE) was supplemented to ewes, and milk yield and fat content-fatty acid (FA) and phospholipid (PL) composition-were monitored. CPE-fed ewes had higher milk yield, and fat, protein and lactose contents than controls. Milk PL content-20% higher in the CPE-supplemented group-was regulated by treatment and not by total fat content; milk phosphatidylethanolamine and phosphatidylcholine increased by 22 and 26%, respectively, in CPE-supplemented vs. control ewes. Milk saturated FA concentration was higher, and total polyunsaturated and monounsaturated FA content lower in the CPE vs. control group, regardless of milk total fat content. CPE supplementation increased milk antioxidant capacity, suggesting antioxidant transfer from dietary source to milk, increasing stability and nutritive value. Our study provides first evidence for milk quality improvement in terms of antioxidants and PL enrichment without compromising total milk fat, suggesting strategies to improve dairy animals' milk composition without compromising total production.

Effect of fixed orthodontic appliances on nonmicrobial salivary parameters

OBJECTIVES:

To examine possible changes in the levels of salivary antioxidants, C-reactive protein (CRP), cortisol, pH, proteins, and blood in patients treated with fixed orthodontic appliances.

MATERIALS AND METHODS:

Salivary samples from 21 orthodontic patients who met specific inclusion criteria were collected before the beginning of orthodontic treatment (T0; baseline), 1 hour after bonding (T1), and 4-6 weeks after bonding (T2). Oxidant-scavenging ability (OSA) was quantified using a luminol-dependent chemiluminescence assay. Cortisol and CRP levels were measured using immunoassay kits. pH levels and presence of proteins and blood in the samples were quantified using strip-based tests.

RESULTS:

A significant decrease in salivary pH was observed after bonding ( P = .013). An increase in oxidant-scavenging abilities during orthodontic treatment was detected, but the change was not statistically significant. Cortisol and CRP levels slightly increased after bonding, but the difference was small without statistical significance. Changes in the presence of proteins and blood were also insignificant.

CONCLUSIONS:

Exposure to fixed orthodontic appliances did not show a significant effect on salivary parameters related to inflammation or stress, with the exception of a significant but transient pH decrease after bonding.

Combined antioxidant effects of Neem extract, bacteria, red blood cells and Lysozyme: possible relation to periodontal disease

Background

The common usage of chewing sticks prepared from Neem tree (Azadirachta indica) in India suggests its potential efficacy in periodontal diseases. The objective of this study is to explore the antibacterial effects of Neem leaf extract on the periodontophatic bacteria Porphyromonas gingivalis and Fusobacterium nucleatum, and its antioxidant capacities alone and in combination with bacteria and polycationic peptides that may be at the site of inflammation.

Methods

Neem leaf extract was prepared by ethanol extraction. The growth kinetics of P. gingivalis and F. nucleatum under anaerobic conditions in the presence of Neem leaf extract were measured. Broth microdilution test was used to determine the Minimal Inhibitory Concentration (MIC) of Neem leaf extract against each bacterial strain. The effect of Neem leaf extract on the coaggregation of the bacteria was assessed by a visual semi-quantitative assay. The antioxidant capacities of Neem leaf extract alone and in combination with bacteria, with the addition of red blood cells or the polycationic peptides chlorhexidine and lisozyme, were determined using a chemiluminescence assay.

Results

Neem leaf extract showed prominent dose-dependent antibacterial activity against P. gingivalis, however, had no effect on the growth of F. nucleatum nor on the coaggregation of the two bacteria. Yet, it showed intense antioxidant activity, which was amplified following adherence to bacteria and with the addition of red blood cells or the polycationic peptides.

Conclusions

Neem leaf extract, containing polyphenols that adhere to oral surfaces, have the potential to provide long-lasting antibacterial as well as synergic antioxidant activities when in complex with bacteria, red blood cells and lisozyme. Thus, it might be especially effective in periodontal diseases.

Thiazolidinedione-8 Alters Symbiotic Relationship in C. albicans-S. mutans Dual Species Biofilm

The small molecule, thiazolidinedione-8 (S-8) was shown to impair biofilm formation of various microbial pathogens, including the fungus Candida albicans and Streptococcus mutans. Previously, we have evaluated the specific molecular mode of S-8 action against C. albicans biofilm-associated pathogenicity. In this study we investigated the influence of S-8 on dual species, C. albicans-S. mutans biofilm. We show that in the presence of S-8 a reduction of the co-species biofilm formation occurred with a major effect on C. albicans. Biofilm biomass and exopolysaccharide (EPS) production were significantly reduced by S-8. Moreover, the agent caused oxidative stress associated with a strong induction of reactive oxygen species and hydrogen peroxide uptake inhibition by a mixed biofilm. In addition, S-8 altered symbiotic relationship between these species by a complex mechanism. Streptococcal genes associated with quorum sensing (QS) (comDE and luxS), EPS production (gtfBCD and gbpB), as well as genes related to protection against oxidative stress (nox and sodA) were markedly upregulated by S-8. In contrast, fungal genes related to hyphae formation (hwp1), adhesion (als3), hydrophobicity (csh1), and oxidative stress response (sod1, sod2, and cat1) were downregulated in the presence of S-8. In addition, ywp1 gene associated with yeast form of C. albicans was induced by S-8, which is correlated with appearance of mostly yeast cells in S-8 treated dual species biofilms. We concluded that S-8 disturbs symbiotic balance between C. albicans and S. mutans in dual species biofilm.

Chlorhexidine markedly potentiates the oxidants scavenging abilities of Candida albicans

The oxidant scavenging ability (OSA) of catalase-rich Candida albicans is markedly enhanced by chlorhexidine digluconate (CHX), polymyxin B, the bile salt ursodeoxycholate and by lysophosphatidylcholine, which all act as detergents facilitating the penetration of oxidants and their intracellular decomposition. Quantifications of the OSA of Candida albicans were measured by a highly sensitive luminol-dependent chemiluminescence assay and by the Thurman's assay, to quantify hydrogen peroxide (H2O2). The OSA enhancing activity by CHX depends to some extent on the media on which candida grew. The OSA of candida treated by CHX was modulated by whole human saliva, red blood cells, lysozyme, cationic peptides and by polyphenols. Concentrations of CHX, which killed over 95 % of Candida albicans cells, did not affect the cells' abilities to scavenge reactive oxygen species (ROS). The OSA of Candida cells treated by CHX is highly refractory to H2O2 (50 mM) but is strongly inhibited by hypochlorous acid, lecithin, trypan blue and by heparin. We speculate that similarly to catalase-rich red blood cells, Candida albicans and additional catalase-rich microbiota may also have the ability to scavenge oxidants and thus can protect catalase-negative anaerobes and facultative anaerobes cariogenic streptococci against peroxide and thus secure their survival in the oral cavity.

The Antioxidant Effect of Fermented Papaya Preparation in the Oral Cavity

Oxidative stress has been recognized to play important roles in various diseases, including of the oral cavity. However, nutritional supplementation of antioxidants to ameliorate the consequences of oxidative stress is debatable. One caveat is that oxidative status is often measured under non-physiological conditions. Here, we investigated the antioxidant potential of fermented papaya preparation (FPP), a product of yeast fermentation of Carica papaya Linn, under conditions that prevail in the oral cavity. Employing highly sensitive luminol-dependent chemiluminescence assays, we show that its antioxidant capacity was augmented by saliva (up to 20-fold, p < 0.0001, at 10 mg) and its components (mucin, albumin) as well as by red blood cells (RBC) and microorganisms present in the normal and pathological environment of the oral cavity. Polyphenols are major plant antioxidants. Using the Folin-Ciocalteu's assay, a very low amount of phenols was measured in FPP suspended in a salt solution. However, its suspension in saliva, albumin, mucin or RBC produced up to sixfold increase, p < 0.001, compared with the sum of polyphenols assayed separately. The results suggested that these enhancing effects were due to the solubilization of antioxidant polyphenols in FPP by saliva proteins and the binding to RBC and microorganisms, thus increasing their availability and activity. Copyright © 2015 John Wiley & Sons, Ltd.

Recent development of multifunctional agents as potential drug candidates for the treatment of Alzheimer's disease

Alzheimer's disease (AD) is a complex and progressive neurodegenerative disorder. The available therapy is limited to the symptomatic treatment and its efficacy remains unsatisfactory. In view of the prevalence and expected increase in the incidence of AD, the development of an effective therapy is crucial for public health. Due to the multifactorial aetiology of this disease, the multi-target-directed ligand (MTDL) approach is a promising method in search for new drugs for AD. This review updates information on the development of multifunctional potential anti-AD agents published within the last three years. The majority of the recently reported structures are acetylcholinesterase inhibitors, often endowed with some additional properties. These properties enrich the pharmacological profile of the compounds giving hope for not only symptomatic but also causal treatment of the disease. Among these advantageous properties, the most often reported are an amyloid-β antiaggregation activity, inhibition of β-secretase and monoamine oxidase, an antioxidant and metal chelating activity, NOreleasing ability and interaction with cannabinoid, NMDA or histamine H3 receptors. The majority of novel molecules possess heterodimeric structures, able to interact with multiple targets by combining different pharmacophores, original or derived from natural products or existing therapeutics (tacrine, donepezil, galantamine, memantine). Among the described compounds, several seem to be promising drug candidates, while others may serve as a valuable inspiration in the search for new effective therapies for AD.

The oxidant scavenging capacity of the oral Mycoplasma salivarium

OBJECTIVE

Mycoplasma salivarium is a human oral potential pathogen that preferentially resides in dental plaques and gingival sulci. It has been suggested that this organism may play an etiological role in inflammatory processes in the oral cavity. The aim of this work was to determine whether M. salivarium possesses a potent oxidant scavenging capacity (OSC).

DESIGN

The OSC of M. salivarium was quantified by a highly sensitive luminal-dependent chemiluminescence assay in the presence of cocktails that induced a constant flux of luminescence resulting from the generation of peroxide, hydroxyl radical (cocktail A) and NO, superoxide and peroxynitrites (cocktail B).

RESULTS

M. salivarium markedly reduced oxidative stress by scavenging both free reactive oxygen and nitrogen species. The OSC of M. salivarium was much higher than that of other Mycoplasma species. Most of M. salivarium OSC was confined to the cytosolic fraction and was markedly increased in the presence of tannic acid, red blood cells or mucin. The cytosolic OSC of M. salivarium was heat stable and not affected by sodium azide or prolonged proteolysis. However, it was markedly decreased upon dialysis, suggesting that the major reducing activity is not enzymatic but rather, a low molecular weight compound(s).

CONCLUSIONS

The ability of M. salivarium to scavenge oxidants may play a role in the survival and pathogenicity of this microorganism. The enhanced OSC of M. salivarium in the presence of tannic acid, red blood cells or mucin might have a significant importance to assess complex interactions with polyphenols from nutrients, salivary proteins and red blood cells extravasated from injured capillaries during infection and inflammation in oral tissues.

Triphala (PADMA) extract alleviates bronchial hyperreactivity in a mouse model through liver and spleen immune modulation and increased anti-oxidative effects

OBJECTIVES

Triphala (TRP), a herbal extract from Tibetan medicine, has been shown to affect lymphocytes and natural killer T (NKT) cell function. We hypothesize that TRP could ameliorate bronchial hyperreactivity through immune-cell modulations.

METHODS

Asthma mouse models were generated through intraperitoneal (IP) injections of ovalbumin (OVA)/2 weeks followed by repeated intranasal OVA challenges. Mice were then treated with normal saline (OVA/NS) or Triphala (OVA/TRP). Data were compared with mice treated with inhaled budesonide. All groups were assessed for allergen-induced hyperreactivity; lymphocytes from lungs, livers and spleens were analyzed for OVA-induced proliferation and their alterations were determined by flow cytometry. Oxidative reactivity using chemiluminescence, serum anti-OVA antibodies level and lung histology were assessed.

RESULTS

Both TRP and budesonide significantly ameliorated functional and histological OVA-induced bronchial hyperreactivity. TRP had no effect on serum anti-OVA antibodies as compared with decreased levels following budesonide treatment. Furthermore, a significant increase in lung and spleen CD4 counts and a decrease in the liver were noted after TRP treatments. Bronchoalveolar fluid from TRP-treated animals but not from the budesonide-treated animals showed anti-oxidative effects.

CONCLUSION

TRP and budesonide caused a significant decrease in bronchial reactivity. TRP treatment altered immune-cell distributions and showed anti-oxidative properties. These findings suggest that immune-cell modulation with TRP can ameliorate lung injury.

Protein deprivation attenuates Hsp expression in fat tissue

For ruminants, dietary protein is the first limiting component to the utilization of low-quality forage. Throughout gestation, low-protein intake may result in prenatal programming that causes various metabolic disturbances and physiological modulations to dams and their developing embryos. We studied the effect of long-term low-protein diet (LPD) on physiological, biochemical, and molecular parameters of the energy status in gestating beef cows. LPD resulted in significant reductions in feed intake and heart rate and promoted a negative retained energy status already after 3 weeks. Elevated levels of plasma creatinine and non-esterified fatty acids indicate endogenous degradation of fat and protein as a response to the demands in energy and nitrogen. Increasing levels of β-hydroxybutyrate confirmed the negative energy status obtained by the physiological measurements. At the molecular level, subcutaneous fat, Hsp90, Hsp70, and proteasome subunits decreased significantly after 3 months on LPD, in parallel with an increase of adipocyte fatty acid-binding protein. These results may indicate a decrease in turn-over of proteins, at the cost of induced lipolysis, and suggest that the response to protein deprivation, when examined in an energy-storing tissue, includes downregulation of the constitutive heat shock proteins involved in the protein degradation pathway of energy production and upregulation of tissue-specific genes such as those involved in energy production from fat degradation.

Visible light promotes interleukin-10 secretion by sublethal fluences

OBJECTIVE

To determine the effect of blue light on cultured splenocyte viability and secretion of cytokines involved in the regulation of immune responses in the inflammatory process.

BACKGROUND DATA

Previous studies showed that red light has various effects on lymphocyte proliferation and production of cytokines.

MATERIALS AND METHODS

Cultured mouse splenocytes were exposed to visible light (wavelengths, 450-490 nm) using 2-108 J/cm(2), with and without scavengers of reactive oxygen species (ROS). One half of the samples were stimulated by the heat-killed periopathogenic bacterium Porphyromonas gingivalis. Following incubation for 48 h, the levels of the cytokines interleukin-10 (IL-10), tumor necrosis factor alpha (TNFα), and interferon gamma (IFNγ) were analyzed, and the viability of the cells was tested using the XTT assay. The total oxidant-scavenging capacity of the nonexposed and exposed splenocytes to light was determined by a chemiluminescence assay, and the temperature of the cell culture medium was measured after light exposure.

RESULTS

Exposure to blue light at fluences of 27-108 J/cm(2) caused a decrease in splenocyte viability. Lower fluences increased the secretion of cytokine IL-10, which was abolished by ROS scavengers. Exposure to light had no effect on the secretion of cytokines TNFα and IFNγ. Following exposure to light, more ROS were detected and the temperature measured did not exceed 30.7°C.

CONCLUSIONS

Blue light had a stimulatory effect on cell secretion of IL-10, mediated by ROS. Therefore, an increase in IL-10 might be a potential method for modulating the inflammatory processes of local disorders, such as periodontitis and arthritis.

The herbal preparation Padma® 28 protects against neurotoxicity in PC12 cells

Padma® 28 is a multicompound herbal preparation based on the camphor formulas from traditional Tibetan medicine (TTM). It contains a variety of different secondary plant substances, which include terpenes and polyphenols such as flavonoids and tannins. As a rich source of antioxidant polyphenols, this herbal Padma 28 preparation seems to be a promising candidate for the treatment of degenerative diseases such as Alzheimer's disease (AD), a condition involving oxidative stress. Moreover, polyphenols have also been shown to mitigate AD neuropathology. The study investigated the protective effect of Padma 28 and of certain polyphenols on the neurotoxicity of PC12 cells induced by the neurotoxins: amyloid-beta (Aβ), glutamate, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 3-nitropropionate (3-NP), known to be involved in AD, Parkinson's disease (PD), amyotrophic-lateral-sclerosis (ALS) and Huntington's disease (HD), respectively. The decrease in cell viability induced by each of the toxins was significantly attenuated by Padma 28 treatment. Also, a decrease in the oxidative capacity of PC12 cells treated with Padma 28 was noted, indicating that the decrease in cell viability induced by the toxins might have been the result of an oxidative stress which could be attenuated by Padma 28 acting as a potent antioxidant. Padma 28, which is available in Europe and USA, seems to be a promising candidate for the treatment of CNS diseases.

Microbial and host cells acquire enhanced oxidant-scavenging abilities by binding polyphenols

The dilemma whether supplementations of dietary antioxidants might prevent the adverse consequences of oxidative stress, the inadequacy of the analytical methods employed to quantify oxidant scavenging ability (OSA) levels in whole blood and the distribution and fate of polyphenols and their metabolites in various body compartments following oral consumption are discussed. While none-metabolized polyphenols might exert their antioxidant effects mainly in the oral cavity, metabolized polyphenols might be beneficial in the gastrointestinal tract to counteract the toxicity of oxidants and also of the sequelae of inflammatory processes. Although only micromolar amounts of polyphenols and their metabolites eventually reach the blood circulation, these may nevertheless still be highly effective as scavengers of reactive oxygen and nitrogen species because of their ability to synergize with plasma low molecular-weight antioxidants and with albumin. Polyphenols can avidly bind to surfaces of microorganisms and of blood cells to markedly enhance their OSA, therefore the routine quantifications of antioxidant levels conducted in clinical settings should always use catalase-rich whole blood but not as customary, plasma alone. In addition to their antioxidant and metal chelating properties, polyphenols may also act as signaling agents capable of affecting metabolic, inflammatory, autoimmune, carcinogenic and aging processes.

Polyphenols enhance total oxidant-scavenging capacities of human blood by binding to red blood cells

The present study offers a new look at the role of erythrocytes and of erythrocytes–polyphenol complexes as potent ‘sinks’ for reactive oxygen species. We hereby show that human erythrocytes have the capacity not only to carry oxygen, but also to bind avidly to their surfaces a large variety of polyphenol antioxidants, which endows upon such complexes enhanced total oxidant-scavenging capacities (TOSC). This was proven by using confocal microscopy, 2,2-diphenyl-1-picrylhydrazyl radical, Folin-Ciocalteu's reagent, cyclic voltammetry and chemiluminescence techniques. The results presented suggest that the true TOSC of blood is the sum of intracellular antioxidants of red blood cells and other blood cells (mainly due to catalase), the polyphenols bound to their surfaces and the antioxidant agents present in plasma. Since erythrocytes can avidly bind and rapidly remove circulating polyphenols, the rule of the thumb to quantify antioxidants in health and disease processes exclusively in plasma as customary in clinical settings, does not represent the true TOSC of whole blood. We also postulate that circulating erythrocytes and possibly also other blood cells might be constantly coated by polyphenols from supplemented nutrients, which act as antioxidant depots and can thus act as protectors against the harmful consequences of oxidative stress. Further studies are needed to determine the faith of polyphenols in the circulation and their sequestration in the spleen.

Total oxidant-scavenging capacities of plasma from glycogen storage disease type Ia patients as measured by cyclic voltammetry, FRAP and luminescence techniques

It has been suggested that the very low incidence of atherosclerosis in glycogen storage disease type Ia (GSD Ia) subjects might be attributed to elevated levels of uric acid, one of the potent low molecular- weight antioxidants found in plasma. The present communication describes a use of two analytical methods-cyclic voltammetry and ferric reducing ability of plasma-and also two chemiluminescence methods to evaluate the total oxidant-scavenging capacities (TOSC) of plasma from GSD Ia patients. Our results verified the elevation of TOSC in GSD Ia patients and we propose the inclusion of luminescence and cyclic voltammetry assays as reliable methods for estimating TOSC in a variety of clinical disorders. Our findings with the cyclic voltammetry method add support to the assumption that the elevated uric acid levels might be the main contributor to plasma antioxidant capacity and possible protection against atherosclerosis.

Amelioration of hepatic fibrosis via Padma Hepaten is associated with altered natural killer T lymphocytes

Hepatic fibrosis is the end-stage consequence of chronic liver disease, affecting many people worldwide. Unlike the anti-fibrotic effect of natural killer (NK) cells, CD8 and NK T subsets are considered as profibrogenic subsets. Padma Hepaten is a multi-compound herbal preparation derived from Tibetan medicine and has proven efficacy in some clinical trials and tests at the cellular level. In this study, we evaluate the immune efficacy of Padma Hepaten administered intraperitoneally (i.p.) and/or orally in a mice model of hepatic fibrosis. Hepatic fibrosis was induced by 6 weeks of biweekly i.p. carbon tetrachloride (CCl4) injections in male C57Bl6 mice. There were four groups, including naive mice, non-treated fibrotic mice and fibrotic mice treated by Padma Hepaten at weeks 5-6 of fibrosis induction either orally or by i.p. injections. Padma Hepaten was prepared at 10 mg/ml in saline and 250 microl (2.5 mg) were administered four times per week. After week 6, animals were killed. To isolate a Padma Hepaten-associated effect on lymphocytes, splenocytes were harvested from either naive or Padma Hepaten-treated non-fibrotic donors. Isolated splenocytes were therefore reconstituted into two groups of irradiated recipients. Recipients were then administered the same CCl4 regimen. Hepatic fibrosis was determined by sirius red staining of liver sections and by assessment of alpha smooth muscle actin expression compared with beta-actin (both by mRNA as well as the protein liver extract western blotting). Hepatic fibrosis and alanine aminotransferase serum levels were decreased significantly in both Padma Hepaten-treated groups compared with the non-treated fibrotic group. Padma Hepaten treatment was associated with attenuation of lymphocyte subsets in both treated groups. Using a chemiluminescence technique to assess total anti-oxidant capacities (TAC), it was found that both the plasmas and livers of mice treated by CCl4 had significantly higher TAC compared with controls. However, the levels of TAC in animals treated either by CCl4 alone or CCl4 with Padma Hepaten were similar. Adoptive transfer of Padma Hepaten-treated lymphocytes was associated with fibrosis amelioration compared with recipients with naive lymphocytes. CCl4 generates higher levels of anti-oxidant capacities, probably as a response to oxidative stress. Padma Hepaten administration attenuated hepatic fibrogenesis significantly, accompanied by attenuation of lymphocyte but not anti-oxidant capacities.

Bacteria Coated by Polyphenols Acquire Potent Oxidant-Scavenging Capacities

Several microbial species, including probiotic lactic acid bacteria, have the ability to irreversibly bind a large variety of polyphenols (flavonoids) and anthocyanidins found in many colored fruits and vegetables and to enhance their total oxidant-scavenging capacities (TOSC). The binding of flavonoids to microbial surfaces was further increased by the cationic polyelectrolytes ligands poly-L-histidine, chlorhexidine and Copaxone®. This phenomenon was confirmed visually, by the FRAP, DPPH, cyclic voltammetry, Folin-Ciocalteu as well as by luminol-dependent chemiluminescence techniques employed to assay TOSC. The possibility is considered that clinically, microbial cells in the oral cavity and in the gastro intestinal tract, complexed with antioxidant polyphenols from nutrients and with cationic ligands, might increase the protection of mammalian cells against damage induced by excessive generation of reactive oxygen species during infections and inflammation.

MICROVASCULAR PERSPECTIVE OF OXYGEN-CARRYING AND -NONCARRYING BLOOD SUBSTITUTES

The development of an alternative to natural blood has evolved from the initial goal of replicating blood properties to the current objective of formulating a fluid that can be used to replace blood while preserving microvascular function and delivering oxygen. The properties of this fluid are counterintuitive and different from blood because it has high viscosity, oxygen affinity, and a low oxygen carrier concentration when compared with blood. The optimal oxygen carrier devised presently is poly-ethylene-conjugated human hemoglobin, a material demonstrated to be vasoinactive and void of the toxicities present in previous hemoglobin formulations. A feature of this material is that it is effective in small quantities, and therefore amplifies the equivalent supply of blood derived from blood donations.