Effect of chitosan on renal function in patients with chronic renal failure

Development and characterization of Polycaprolactone/chitosan-based scaffolds for tissue engineering of various organs: A review

Research in creating 3D structures mirroring the extracellular matrix (ECM) with accurate environmental cues holds paramount significance in biological applications.Biomaterials that replicate ECM properties-mechanical, physicochemical, and biological-emerge as pivotal tools in mimicking ECM behavior.Incorporating synthetic and natural biomaterials is widely used to produce scaffolds suitable for the intended organs.Polycaprolactone (PCL), a synthetic biomaterial, boasts commendable mechanical properties, albeit with relatively modest biological attributes due to its hydrophobic nature.Chitosan (CTS) exhibits strong biological traits but lacks mechanical resilience for complex tissue regeneration.Notably, both PCL and CTS have demonstrated their application in tissue engineering for diverse types of tissues.Their combination across varying PCL:CTS ratios has increased the likelihood of fabricating scaffolds to address defects in sturdy and pliable tissues.This comprehensive analysis aspires to accentuate their distinct attributes within tissue engineering across different organs.The central focus resides in the role of PCL:CTS-based scaffolds, elucidating their contribution to the evolution of advanced functional 3D frameworks tailored for tissue engineering across diverse organs.Moreover, this discourse delves into the considerations pertinent to each organ.

The effect of insulin-loaded gold and carboxymethyl chitosan nanoparticles on gene expression of glucokinase and pyruvate kinase in rats with diabetes type 1

The goal of this study was to see how effective subcutaneous (SC) insulin is and two different types of oral insulin-loaded nanoparticles (INS) including carboxymethyl chitosan nanoparticles (CMCNPs) and gold nanoparticles (AuNPs) separately and compare their effects on glucokinase, pyruvate kinase gene expressions, and other parameters in diabetes type one male Wistar rats. Seven groups of ten male Wistar rats for each group were formed at random including four control groups (n = 10) and three treatment groups (n = 10). The control groups consisted of four control groups (10 rats for each) and three treatment groups (10 rats for each). Normal control rats were not given any treatment, as were diabetic rats that were not given any treatment, and diabetic rats that were given oral nanoparticles (CMCNPs and AuNPs). Diabetic rats were given subcutaneous insulin, oral insulin-loaded carboxymethyl chitosan nanoparticles (INS-CMCNPs), and oral insulin-loaded gold nanoparticles (INS-AuNPs). The rats were treated for the final 3 weeks of the experiment, which lasted 4 weeks. CMCNPs and AuNPs presented a promising effect on pyruvate kinase and Glucokinase gene expressions compared to subcutaneous insulin. We also discovered that conjugating insulin to CMCNPs and AuNPs protects them from the insulin-degrading enzyme, which offers managed bioavailability. Furthermore, we investigated the effects of CMCNPs and AuNPs on several parameters and discovered that both have a significant effect in vivo, which enables glucose level regulation, and improves patient organ activity for better glucose consumption. PRACTICAL APPLICATIONS: In this paper, we discussed the effect of oral INS-CMCNPs and INS-AuNPs, and compared their effects on Glucokinase and pyruvate kinase gene expressions and other biochemical parameters in diabetes type one male Wistar rats. On the other hand, we investigated the impact of oral INS and subcutaneous insulin separately on the same parameters and their effect on the histology of the liver and pancreas of diabetic rats. According to our research, as we discussed the different mechanisms of INS-CMCNPs and INS-AuNPs, they presented a promising effect compared to SC insulin. They can be used to keep oral insulin safe from the environment of the gastrointestinal system to overcome all the barriers, improve the therapeutic, and clinical outcomes of insulin by maintaining its desired concentration inside the body, ending the panic of the patient from receiving insulin by the SC injection by increasing his satisfaction with receiving accurate oral insulin doses.

Effect of a Novel Hybrid Nanocomposite of Cisplatin-Chitosan on Induced Tissue Injury as a Suggested Drug by Reducing Cisplatin Side Effects

The self-assembly of cisplatin (Cis-Pt) and chitosan nanoparticles (Cs NPs) has been synthesized and characterized successfully by different analyses and techniques, such as scanning electron microscopy, ultraviolet-visible spectrophotometry, and Fourier transform infrared spectroscopy. The efficiency of loading Cis-Pt on Cs NPs for decreasing the side effects of Cis-Pt by loading it on Cs NP surface was revealed through histopathological and physiological measurements for the liver, testis, and kidney cells. Self-assembly hybrid nanocomposite (Cis-Pt@Cs) could improve spermatogenic cells, seminiferous tubules, and Leydig cells in the interstitial tissue. Kidney examination showed intact glomeruli with a mild increase in capsular space in addition to the intact renal tubular epithelial lining, and liver findings showed improvement in dilation and congestion of the central vein besides mild dilation of blood sinusoids in addition to a mild degree of hepatocyte vacuolation. The serum levels of hepatic, renal, and testicular marker analysis were measured, where Cis-Pt increased the serum levels of alanine aminotransferase, aspartate aminotransferase activity, urea, creatinine, and decreased testosterone levels, while synthesized self-assembly appeared normalized levels. From the results, the self-assembly hybrid nanocomposite decreases and improves the side effects of Cis-Pt.

Iron-based phosphorus chelator: Risk of iron deposition and action on bone metabolism in uremic rats

Phosphate chelators are frequently used in patients with chronic kidney disease (CKD). New iron-based chelators remain understudied and offer a promising therapeutic option for the control of bone and mineral disorders of chronic kidney disease (BMD-CKD). We assessed the effect of the phosphorus chelator, chitosan-iron III (CH-FeCl), compared to calcium carbonate (CaCO₃) in BMD-CKD and the potential iron overload in uremic rats. Thirty-two animals were divided into four groups, namely the control, CKD, CKD/CH-FeCl, and CKD/CaCO₃ groups. CKD was induced by adding 0.75% (4 weeks) and 0.1% (3 weeks) adenine to the diet. The chelators were administered from week 3 through week 7. The renal function, BMD-CKD markers, and histomorphometry of the femur were assessed at week 7. The CKD group showed a significant increase in creatinine (83.9 ± 18.6 vs. 41.5 ± 22.1 µmol/L; P = 0.001), phosphate (3.5 ± 0.8 vs. 2.2 ± 0.2 mmol/L; P = 0.001), fractional excretion of phosphorus (FEP) (0.71 ± 0.2 vs. 0.2 ± 0.17; P = 0.0001), and FGF23 (81.36 ± 37.16 pg/mL vs. 7.42 ± 1.96; P = 0.011) compared to the control group. There was no accumulation of serum or bone iron after the use of CH-FeCl. The use of chelators reduced the FEP (control: 0.71 ± 0.20; CKD/CH-FeCl: 0.40 ± 0.16; CKD/CaCO₃ 0.34 ± 0.15; P = 0.001), without changes in the serum FGF23 and parathyroid hormone levels. Histomorphometry revealed the presence of bone disease with high remodeling in the uremic animals without changes with the use of chelators. The CH-FeCl chelator was efficient in reducing the FEP without iron accumulation, thereby paving the way for the use of this class of chelators in clinical settings in the future.

The dietary supplement chitosan lowers serum phosphorus in a hemodialysis patient not tolerating prescription medications

Chitosan is a widely available, nontoxic, biodegradable biopolymer that binds negatively charged molecules. Its use as a dietary supplement for weight loss derives from its purported ability to bind negatively charged lipids and bile acids and prevent their gastrointestinal absorption. Here, we report the case of a dialysis patient who did not tolerate prescription phosphorus binders and who has been able to control her serum phosphorus levels for a year by taking 3.5 g of chitosan a day with meals. A quantitative analysis shows that chitosan may bind between 16 and 41 mg of phosphorus per gram, comparable to prescription binders. Chitosan may provide an over-the-counter alternative as non-calcium phosphorus binder for patients not tolerating prescription phosphorus binders because of side effects, cost, or efforts to limit their medication burden.

Formulation and Evaluation of Solid Dispersion Chitosan Tablet from Whiteleg Shrimp (Litopenaeus vannamei) Using PVP K-30 As a Carriers

Whiteleg shrimp (Litopenaeus vannamei) on the market are processed or sold only to take part in the meat. The head, shell, and tail are thrown away without any prior processing. Underutilized waste causes environmental problems. An alternative to overcome this environmental disturbance phenomenon is to utilize shrimp shells containing chitin and subsequently transformed into chitosan that can be applied in various fields. Chitosan has poor solubility in water but high permeability, so to improve bioavailability is by making solid dispersions. Chitosan solid dispersion made by the solvent evaporation technique used PVP K-30 as the carriers. The result of chitosan solid dispersion was then molded into tablets by the direct compression method. Hence the tablets were evaluated by weight and size uniformity, hardness, friability, and disintegration time. The formulation divided into three groups, that is F1 (chitosan : PVP K-30 = 1 : 1 solid dispersion), F2 (chitosan : PVP K-30 = 1 : 3 solid dispersion), and F3 (pure chitosan). All the formulas by weight and size uniformity and disintegration time fulfill the requirements. F3 hardness is 4,275 kg is the best from F1 and F2. By statistic analytical from weight uniformity, hardness and disintegration time give significant difference with sig. <0,05.

Novel Potential Application of Chitosan Oligosaccharide for Attenuation of Renal Cyst Growth in the Treatment of Polycystic Kidney Disease

Chitosan oligosaccharide (COS), a natural polymer derived from chitosan, exerts several biological activities including anti-inflammation, anti-tumor, anti-metabolic syndrome, and drug delivery enhancer. Since COS is vastly distributed to kidney and eliminated in urine, it may have a potential advantage as the therapeutics of kidney diseases. Polycystic kidney disease (PKD) is a common genetic disorder characterized by multiple fluid-filled cysts, replacing normal renal parenchyma and leading to impaired renal function and end-stage renal disease (ESRD). The effective treatment for PKD still needs to be further elucidated. Interestingly, AMP-activated protein kinase (AMPK) has been proposed as a drug target for PKD. This study aimed to investigate the effect of COS on renal cyst enlargement and its underlying mechanisms. We found that COS at the concentrations of 50 and 100 µg/mL decreased renal cyst growth without cytotoxicity, as measured by MTT assay. Immunoblotting analysis showed that COS at 100 µg/mL activated AMPK, and this effect was abolished by STO-609, a calcium/calmodulin-dependent protein kinase kinase beta (CaMKKβ) inhibitor. Moreover, COS elevated the level of intracellular calcium. These results suggest that COS inhibits cyst progression by activation of AMPK via CaMKKβ. Therefore, COS may hold the potential for pharmaceutical application in PKD.

Effects of the Dietary Inclusion of Partially Defatted Black Soldier Fly (Hermetia illucens) Meal on the Blood Chemistry and Tissue (Spleen, Liver, Thymus, and Bursa of Fabricius) Histology of Muscovy Ducks (Cairina moschata domestica)

Simple Summary

Insects represent a promising feed ingredient for poultry diets, as an alternative to conventional feedstuffs. Black soldier fly (BSF; Hermetia illucens) larvae are processed to obtain two main products: the protein and fat fractions. The possible utilization of BSF defatted meal in Muscovy duck (Cairina moschata domestica) diets has been poorly investigated. However, its effect on in vivo and post-mortem traits, which are extremely important for animal welfare, has not yet been investigated. Therefore, the present study has evaluated the effect of 0%, 3%, 6%, and 9% dietary BSF meal replacement on the in vivo haematological parameters and on the post-mortem organ traits. Overall, the obtained results are encouraging as increasing dietary BSF meal did not impair the growth performance or the haematological traits. Furthermore, both the liver and renal function were unaffected or even improved. The antioxidant picture appeared improved and the histological traits were not influenced by the dietary inclusion of BSF meal. From a productive and biological point of view, the dietary replacement up to 9% of BSF meal in Muscovy duck diet is feasible and BSF meal could represent a promising feed ingredient.

Abstract

The present study has evaluated the effects of dietary partially-defatted black soldier fly (BSF; Hermetia illucens L.) larva meal on the blood parameters, antioxidant status, and histological features of the organs of broiler ducks. A total of 192 female 3-days of age Muscovy ducklings (Cairina moschata domestica) were divided into four dietary treatments (0%, 3%, 6%, and 9% BSF meal inclusion; 6 pens/treatment, 8 birds/pen). A total of 12 ducks/treatment (2 birds/pen) were slaughtered at 51 days of age and blood samples were collected to evaluate the haematological traits, serum protein, lipid and minerals, liver and renal function serum enzymes, plasma oxidative enzymes, and metabolites. Liver, spleen, thymus, and bursa of Fabricius samples were submitted to histopathological investigations. Between the serum and plasma traits, triglycerides, cholesterol, creatinine, alkaline phosphatase, magnesium, malondialdehyde, and nitrotyrosine showed a linear decrease for increasing amounts of dietary BSF meal (p <0.01); in contrast, the serum iron concentration showed a linear increase (p <0.01). Moreover, the histopathological findings were not significantly affected by the dietary BSF larva meal inclusion. The results showed that the inclusion of up to 9% BSF larva meal represents a promising feed ingredient for Muscovy duck nutrition, and improved blood traits were observed.

Beneficial Effect of Dietary Fiber on Hyperuricemia in Rats and Humans: A Review

Hyperuricemia is recognized as a lifestyle-related disease and the prevalence is increasing in many parts of the world. Excessive intake of purines increases serum uric acid concentration and is thought to be one factor causative of hyperuricemia. Therefore, it is thought that prevention of hyperuricemia by dietary control may be very important. This is an article of our basic research regarding the role of dietary fiber in the suppression of hyperuricemia induced by dietary purines in rats; in addition, clinical research suggesting the possibility that dietary fiber intake has a beneficial effect on the prevention or suppression of hyperuricemia in humans is discussed. Our own studies reveal that the test dietary fiber significantly suppresses the elevation of serum uric acid concentration induced by dietary RNA (12.3-46.2%), adenosine-5'-monophosphate (9.5-23.2%), adenosine (10.7-20.4%), or adenine (16.3-38.9%) and suppresses experimental hyperuricemia in rats. The mechanism is presumed to be mediated by suppression of the digestion and/or absorption of dietary purines by dietary fiber. In clinical studies, intake of dietary fiber decreases serum uric acid concentrations. Reports of recent epidemiological studies indicate that higher levels of hyperuricemia increase the prevalence of its comorbidities (e.g., chronic kidney disease, obesity, hypertension, diabetes, and cardiovascular disease) and dietary fiber intake is associated with significantly lower risk for hyperuricemia and its comorbidities. We wish to emphasize the importance of recognizing the validity of increased dietary fiber intake as a preventive or suppressive method for hyperuricemia and its comorbidities.

Productive performance and blood profiles of laying hens fed Hermetia illucens larvae meal as total replacement of soybean meal from 24 to 45 weeks of age

The aim of the research was to study the effects of an insect meal from Hermetia illucens larvae (HILM) as complete replacement of soybean meal (SBM) on productive performance and blood profiles of laying hens, from 24 to 45 wk of age. A total of 108 24-week-old Lohmann Brown Classic laying hens was equally divided into 2 groups (54 hens/group, 9 replicates of 6 hens/group). From 24 to 45 wk of age, the groups were fed 2 different isoproteic and isoenergetic diets: the control group (SBM) was fed a corn-soybean meal based diet, while in the HILM group the soybean meal was completely replaced by Hermetia illucens larvae meal. Feed intake, number of eggs produced, and egg weight were recorded weekly along the trial. At 45 wk of age, blood samples were collected from 2 hens per replicate. The use of HIML led to a more favorable (P < 0.01) feed conversion ratio in hens but lay percentage, feed intake, average egg weight, and egg mass were higher (P < 0.01) in hens fed the SBM diet. Hens fed insect meal produced a higher percentage of eggs from small (S), medium (M), and extra-large (XL) classes (P < 0.01) than SBM, while the SBM group had a higher percentage of eggs from the large (L) class (P < 0.01). The levels of globulin and albumin to globulin ratio were, respectively, higher and lower (P < 0.05) in HILM than the SBM group. Cholesterol and triglycerides were higher (P < 0.05 and P < 0.01, respectively) in hens from SBM than in the HILM group. Blood levels of Ca were higher (P < 0.01) in hens fed insect meal, while creatinine was higher (P < 0.01) in blood of hens fed SBM. Hermetia illucens larvae meal can be a suitable alternative protein source for laying hens even if the complete replacement of soybean meal needs further investigation to avoid the negative effects on feed intake.

Bio-evaluation of crustacean and fungal nano-chitosan for applying as food ingredient

Chitosan, bio-polyaminosacharide, is derived from chitin. Two sources (shrimp wastes and fungus biomass) were used to produce chitosan. And then the chitosan was produced in the nano-form followed by characterization by transmission electron microscopy. The images obtained clearly showed that the size of nano-chitosan ranged between 7 and 13 and 3–6 nm with spherical shape for shrimp and fungal sources, respectively. The antimicrobial activities of the tested concentrations of chitosan and nano-chitosan were examined and found to have high activity against the tested pathogens. The evaluation of the toxicity of the tested concentrations of the produced chitosan and its nano-size were performed using brine shrimp and rat bioassay. Toxicity examination of chitosan and their nano derivatives is an essential procedure to assess the possibility of using these concentrations as food ingredient. Nine groups of rats were treated with either chitosan or nano-chitosan of both sources at 100 and 200 mg kg⁻¹ bw. Adding chitosan in the diet of all groups showed no significant changes in both the blood biochemical and oxidative stress parameters when compared with control group. The histopathology of liver, kidney and stomach confirmed the results of the previous parameters. No signs of inflammation, fibrosis or cirrhosis were found in examined organs. It is concluded that chitosan and nano-chitosan of shrimp and Rhizopus stolonifer had high antimicrobial activity and are not toxic in the same time and it can be used as food ingredients.

Growth performance, blood profiles and carcass traits of Barbary partridge (Alectoris barbara) fed two different insect larvae meals (Tenebrio molitor and Hermetia illucens)

To investigate the effect of two insect meals (from Hermetia illucens, HI and Tenebrio molitor, TM larvae) on productive performance and blood profiles of Barbary partridge, ninety, seven days old partridges were divided into 5 groups (6 replicates, 3 partridges/replicate). Up to 64d, the groups fed 5 isoproteic and isoenergetic diets: the control fed a corn-soybean meal diet (SBM group); in TM25 and TM50 groups the 25 and 50% of SBM proteins were substituted by the protein from TM, respectively; in HI25 and HI50 groups the 25 and 50% of SBM were substituted by the protein from HI, respectively. The birds fed TM25 and both the HI levels reached a higher (P<0.01) live weight at 64d than the control. Considering the entire experimental period the TM groups had a more favorable FCR than SBM. The carcass weights of all the insect groups were higher (P<0.01) than the control. The weight of the full digestive tract in SBM group was the highest (P<0.01). The caecal weight, the intestinal and caecal length were the highest (P<0.01) in the SBM group. The SBM group the highest value of albumin/globulin (P<0.01) and creatinine (P<0.05). TM seems to be more effective than HI in improving FCR. The reduced albumin/globulin ratio in the insect meal fed groups could be ascribed to the chitin content and this result was not affected by the amount of chitin intake, suggesting that also the lowest values are able to express their potential effects in partridges.

Characterization of a Chitosanase from Jelly Fig (Ficus awkeotsang Makino) Latex and Its Application in the Production of Water-Soluble Low Molecular Weight Chitosans

A chitosanase was purified from jelly fig latex by ammonium sulfate fractionation (50–80% saturation) and three successive column chromatography steps. The purified enzyme was almost homogeneous, as determined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and gel activity staining. The molecular mass of the enzyme was 20.5 kDa. The isoelectric point (pI) was <3.5, as estimated by isoelectric focusing electrophoresis on PhastGel IEF 3-9. Using chitosan as the substrate, the optimal pH for the enzyme reaction was 4.5; the kinetic parameters K_m and V_max were 0.089 mg mL^-1 and 0.69 μmol min^-1 mg^-1, respectively. The enzyme showed activity toward chitosan polymers which exhibited various degrees of deacetylation (21–94%). The enzyme hydrolyzed 70–84% deacetylated chitosan polymers most effectively. Substrate specificity analysis indicated that the enzyme catalyzed the hydrolysis of chitin and chitosan polymers and their derivatives. The products of the hydrolysis of chitosan polymer derivatives, ethylene glycol (EG) chitosan, carboxymethyl (CM) chitosan and aminoethyl (AE) chitosan, were low molecular weight chitosans (LMWCs); these products were referred to as EG-LMWC, CM-LMWC and AE-LMWC, respectively. The average molecular weights of EG-LMWC, CM-LMWC and AE-LMWC were 11.2, 11.2 and 8.89 kDa, respectively. All of the LMWC products exhibited free radical scavenging activities toward ABTS^•+, superoxide and peroxyl radicals.

Low-molecular-weight chitosan scavenges methylglyoxal and N (ε)-(carboxyethyl)lysine, the major factors contributing to the pathogenesis of nephropathy

Methylglyoxal (MG) can cause protein glycation, resulting in cell damage and dysfunction. Accumulation of MG and its downstream metabolite N^ε-(carboxyethyl)lysine (CEL) has been identified in several variations of nephropathy, including diabetic, hypertensive, and gentamicin-induced nephropathies. In this study, we investigated the effects of low-molecular-weight chitosan (lmw-chitosan) on MG-induced carbonyl stress in aristolochic acid-induced nephropathy. We used a buffer to investigate whether MG could be scavenged by lmw-chitosan in vitro. In addition, we also used a mouse model of aristolochic acid-induced nephropathy, which exhibits 12-fold greater accumulation of MG in the kidneys than that found in control animals, to examine whether lmw-chitosan could decrease MG levels in vivo. Examination of the binding of lmw-chitosan with MG in vitro demonstrated that the concentration of lmw-chitosan necessary to achieve 50% inhibition was 4.60 µg mL⁻¹. Treatment with lmw-chitosan (500 mg kg⁻¹ day⁻¹ orally) for 14 days significantly decreased renal MG accumulation from 212.86 ± 24.34 to 86.15 ± 33.79 µg g⁻¹ protein (p < 0.05) and CEL levels from 4.60 ± 0.27 to 2.84 ± 0.28 µmol µg⁻¹ protein (p < 0.05) in the aristolochic acid-induced nephropathy model. These data suggest that lmw-chitosan might represent a novel treatment modality for MG-related diseases such as nephropathy.

Chitosan Prevents Gentamicin-Induced Nephrotoxicity via a Carbonyl Stress-Dependent Pathway

Aminoglycosides are widely used to treat infections; however, their applications are limited by nephrotoxicity. With the increase of antibiotic resistance, the use of aminoglycosides is inevitable. Low-molecular-weight chitosan (LMWC) has shown renal protective effects in dialysis patients. However, no study has evaluated LMWC for preventing aminoglycoside-induced nephrotoxicity or determined the mechanisms underlying the renal protective effects. In this study, LMWC (165 or 825 mg/kg/day) or metformin (100 mg/kg/day) was orally administered for 13 days to rats with nephropathy induced by gentamicin (GM), a kind of aminoglycoside (150 mg/kg/day i.p. for 6 days). Both LMCW doses improved renal function. Serum creatinine levels improved in rats treated with 165 and 825 mg/kg/day LMWC (from 2.14 ± 0.74 mg/dL to 1.26 ± 0.46 mg/dL and 0.69 ± 0.12 mg/dL, resp., P < 0.05). Blood urea nitrogen levels were also improved in these rats (from 73.73 ± 21.13 mg/dL to 58.70 ± 22.71 mg/dL and 28.82 ± 3.84 mg/dL, resp., P < 0.05). Additionally, renal tissue morphology improved after LMWC treatment, and accumulation of renal methylglyoxal, a damage factor associated with carbonyl stress, was reversed. These results show that LMWC prevents GM-induced renal toxicity via a carbonyl stress-dependent pathway.

Effect of chitosan chewing gum on reducing serum phosphorus in hemodialysis patients: a multi-center, randomized, double-blind, placebo-controlled trial

BACKGROUND

HS219 (40 mg chitosan-loaded chewing gum) is designed to bind salivary phosphorus as an add-on to available phosphorus binders. We performed a randomized, placebo-controlled, double-blind study to evaluate the efficacy and safety of HS219 in hemodialysis (HD) patients with hyperphosphatemia as an add-on to phosphorus binders.

METHODS

Sixty-eight HD patients who were maintained on calcium carbonate (n=33) or sevelamer hydrochloride (n=35) were enrolled. The primary end point was a change in serum phosphorus levels. Secondary end points included changes in levels of salivary phosphorus, serum calcium, parathyroid hormone (PTH), and intact fibroblast growth factor (iFGF) 23.

RESULTS

Sixty-three patients chewed either HS219 (n=35) or placebo (n=28) for 30 min, three times a day, for 3 weeks. HS219 was well tolerated and safe. However, HS219 was not superior to placebo with additional reduction of serum phosphorus with respect to phosphorus binders at the end of the chewing period. There were no significant effects of HS219 on reduction of salivary phosphorus, serum calcium, iPTH, or iFGF23 levels.

CONCLUSIONS

The chitosan-loaded chewing gum HS219 does not affect serum and salivary phosphorus levels in Japanese HD patients with hyperphosphatemia. Our findings do not support previous findings that 20 mg of chitosan-loaded chewing gum reduces serum and salivary phosphorus levels.

TRIAL REGISTRATION

[corrected] ClinicalTrials.gov NCT01039428, 24 December, 2009.

Effect of dietary supplements in reducing probability of death for uremic crises in dogs affected by chronic kidney disease (masked RCCT)

Chitosan and alkalinizing agents can decrease morbidity and mortality in humans with chronic kidney disease (CKD). Whether this holds true in dog is not known. Objective of the study was to determine whether a commercial dietary supplement containing chitosan, phosphate binders, and alkalinizing agents (Renal), compared to placebo, reduces mortality rate due to uremic crises in dogs with spontaneous CKD, fed a renal diet (RD). A masked RCCT was performed including 31 azotemic dogs with spontaneous CKD. Dogs enrolled in the study were randomly allocated to receive RD plus placebo (group A; 15 dogs) or RD plus Renal (group B; 16 dogs). During a first 4-week period, all dogs were fed an RD and then randomized and clinically evaluated up to 44 weeks. The effects of dietary supplements on mortality rate due to uremic crises were assessed. At 44 weeks, compared to group A, dogs in group B had approximately 50% lower mortality rate due to uremic crises (P = 0.015). Dietary supplementation with chitosan, phosphate binders, and alkalinizing agents, along with an RD, is beneficial in reducing mortality rate in dogs with spontaneous CKD.

Chitosan for overweight or obesity

BACKGROUND

Chitosan, a deacetylated chitin, is a dietary supplement reported to decrease body weight. It is widely available over the counter worldwide and although evaluated in a number of trials its efficacy remains in dispute.

OBJECTIVES

To assess the effects of chitosan as a treatment for overweight and obesity.

SEARCH STRATEGY

We searched electronic databases (MEDLINE, EMBASE, BIOSIS, CINAHL, The Cochrane Library), specialised web sites (Controlled Trials, IBIDS, SIGLE, Reuter's Health Service, Natural Alternatives International, Pharmanutrients), bibliographies of relevant journal articles, and contacted relevant authors and manufacturers.

SELECTION CRITERIA

Trials were included in the review if they were randomised controlled trials of chitosan for a minimum of four weeks duration in adults who were overweight or obese. Authors of included studies were contacted for additional information where appropriate.

DATA COLLECTION AND ANALYSIS

Details from eligible trials were extracted independently by two reviewers using a standardised data extraction form. Differences in data extraction were resolved by consensus. Continuous data were expressed as weighted mean differences and standard deviations. The pooled effect size was computed by using the inverse variance weighted method.

MAIN RESULTS

Fifteen trials including a total of 1219 participants met the inclusion criteria. No trial to date has measured the effect of chitosan on mortality or morbidity. Analyses indicated that chitosan preparations result in a significantly greater weight loss (weighted mean difference -1.7 kg; 95% confidence interval (CI) -2.1 to -1.3 kg, P < 0.00001), decrease in total cholesterol (-0.2 mmol/L [95% CI -0.3 to -0.1], P < 0.00001), and a decrease in systolic and diastolic blood pressure compared with placebo. There were no clear differences between intervention and control groups in terms of frequency of adverse events or in faecal fat excretion. However, the quality of many studies was sub-optimal and analyses restricted to studies that met allocation concealment criteria, were larger, or of longer duration showed that such trials produced substantially smaller decreases in weight and total cholesterol.

AUTHORS' CONCLUSIONS

There is some evidence that chitosan is more effective than placebo in the short-term treatment of overweight and obesity. However, many trials to date have been of poor quality and results have been variable. Results obtained from high quality trials indicate that the effect of chitosan on body weight is minimal and unlikely to be of clinical significance.

A ninety-day feeding, subchronic toxicity study of oligo-N-acetylglucosamine in Fischer 344 rats

Oligo-N-acetylglucosamine (OAG) is a hydrolyzed derivative of chitin that has been used as a sweetener in foods. Since, no information has been published about the safety of OAG, a 90-day feeding study was conducted, using F344 Fischer rats of both sexes, to characterize and evaluate the toxicity of OAG, and the results of the study are presented here. Dietary levels of 0% (control), 0.2%, 1%, and 5% OAG did not change any measurements in ophthalmological examinations, clinical signs, body weights, food consumption, hematology, blood biochemistry, urinalysis, necropsies, organ weights or histological examinations. The sole finding, which could not be clarified to be attributed to OAG or not, was a decrease in the relative weight of the submaxillary gland to body weight in the male animals given the 5% OAG diet. Although no lesions were found in either gross or histological examination in the present study, further studies using OAG levels higher than 5% might provide a clue to the mechanisms underlying the decreased organ weight observed here. Taken together, under the conditions in the present study, the No Observed Adverse Effect Level (NOAEL) for males was found to be 1% (0.641 g/kg/day); and that for females, 5% (3.64 /kg/day) or more, based on the lack of toxicological effects.

The Systemic Theory of Living Systems. Part IV: Systemic Medicine--The Praxis

This fourth lecture illustrates the praxis and results of Systemic Medicine (SM) in various therapeutic applications. SM's success has made it popular throughout Venezuela and Puerto Rico. The treatment of over 300,000 patients by 150 orthodox MD's, trained and qualified in SM, in 35 medical establishments with above average results corroborate its effectiveness as an eCAM in chronic degenerative diseases. Herein we provide a synopsis of results obtained in four such pathologies-the journal's necessary space restrictions somewhat limiting content-as well as clinical and photographic evidence. The validity of any medical theory is substantiated by its degree of effectivity and success. The workability of evidence-based SM corroborates Systemic Theory's transcendence.

Microcrystalline Chitosan is Ineffective to Decrease Plasma Lipids in both Apolipoprotein E epsilon4 Carriers and Non-Carriers: A Long-Term Placebo-Controlled Trial in Hypercholesterolaemic Volunteers

Chitosan is a deacetylated product of chitin. Microcrystalline form of chitosan has a large adsorption area claimed to decrease gastrointestinal absorption of cholesterol. However, the long-term effect of chitosan on plasma lipids is variable, the averaged influence being negligible or lacking in mildly-to-moderately hypercholesterolaemic (4.8-6.8 mmol/l) subjects. We evaluated whether this variation and inefficacy depend on apolipoprotein E genotype. 130 middle-aged, otherwise healthy men (n=55) and women (n=75) were randomized into two treatment groups for a 7 month trial. During a 1 month run-in period all participants received placebo. Subsequently, one half first took placebo twice daily for 3 months and then 1.2 g chitosan twice daily for 3 months, and the other half vice versa in a cross-over way. Altogether 84 participants completed the study. Plasma lipids and glucose were determined at the end of each phase of the study, and all subjects undergone to the cross-over phases were apolipoprotein E genotyped. Chitosan altered plasma total, low- and high density cholesterol, triglycerides, and blood glucose in neither apolipoprotein E epsilon 4 allele carriers (n=29) nor non-carriers (n=55), compared to placebo. In conclusions, chitosan is ineffective to decrease plasma lipids in apolipoprotein E epsilon 4 carrier and non-carrier phenotypes with mildly-to-moderately increased plasma cholesterol.

Chitosan for overweight or obesity

BACKGROUND

Chitosan, a deacetylated chitin, is a dietary supplement reported to decrease body weight. It is widely available over the counter worldwide and although evaluated in a number of trials its efficacy remains in dispute.

OBJECTIVES

To assess the effects of chitosan as a treatment for overweight and obesity.

SEARCH STRATEGY

We searched electronic databases (MEDLINE, EMBASE, BIOSIS, CINAHL, The Cochrane Library), specialised web sites (Controlled Trials, IBIDS, SIGLE, Reuter's Health Service, Natural Alternatives International, Pharmanutrients), bibliographies of relevant journal articles, and contacted relevant authors and manufacturers. Last searches were completed in March 2004.

SELECTION CRITERIA

Trials were included in the review if they were randomised controlled trials of chitosan a minimum of four weeks duration in adults who were overweight or obese. Authors of included studies were contacted for additional information where appropriate.

DATA COLLECTION AND ANALYSIS

Details from eligible trials were extracted independently by two reviewers using a standardised data extraction form. Differences in data extraction were resolved by consensus. Continuous data were expressed as weighted mean differences and standard deviations. The pooled effect size was computed by using the inverse variance weighted method.

MAIN RESULTS

Fourteen trials including a total of 1131 participants met the inclusion criteria. No trial to date has measured the effect of chitosan on mortality or morbidity. Analyses including all trials indicated that chitosan preparations result in a significantly greater weight loss (weighted mean difference -1.7 kg; 95% confidence interval (CI) -2.1 to -1.3 kg; P < 0.00001), decrease in total cholesterol (-0.2 mmol/L; 95% CI -0.3 to -0.1; P < 0.00001), decrease in systolic (-5.9 mmHg; 95% CI -7.3 to -4.6; P < 0.0001) and diastolic (-3.4 mmHg; 95% CI -4.4 to -2.4; P < 0.00001) blood pressure compared with placebo. There were no clear differences between intervention and control groups in terms of frequency of adverse events or in faecal fat excretion. However, the quality of many studies was sub-optimal and analyses restricted to studies that met allocation concealment criteria, were larger, or of longer duration showed that such trials produced substantially smaller decreases in weight and total cholesterol.

AUTHORS' CONCLUSIONS

There is some evidence that chitosan is more effective than placebo in the short-term treatment of overweight and obesity. However, many trials to date have been of poor quality and results have been variable. Results obtained from high quality trials indicate that the effect of chitosan on body weight is minimal and unlikely to be of clinical significance.

Effect of a chitosan-based hemostatic dressing on blood loss and survival in a model of severe venous hemorrhage and hepatic injury in swine

BACKGROUND

Hemorrhage is a leading cause of death from trauma. An advanced hemostatic dressing could augment available hemostatic methods. We studied the effects of a new chitosan dressing on blood loss, survival, and fluid use after severe hepatic injury in swine.

METHODS

Swine received chitosan dressings or gauze sponges. Standardized, severe liver injuries were induced. After 30 seconds, dressings were applied and resuscitation initiated. Blood loss, hemostasis, resuscitation volume, and 60-minute survival were quantified.

RESULTS

Posttreatment blood loss was reduced ( p< 0.01) in the chitosan group (264 mL; 95% confidence interval [CI], 82-852 mL) compared with the gauze group (2,879 mL; 95% CI, 788-10,513 mL). Fluid use was reduced ( p= 0.03) in the chitosan group (1,793 mL; 95% CI, 749-4,291) compared with the gauze group (6,614 mL; 95% CI, 2,519-17,363 mL). Survival was seven of eight and two of even in the chitosan and gauze groups ( p= 0.04), respectively. Hemostasis was improved in the chitosan group ( p= 0.03).

CONCLUSION

A chitosan dressing reduced hemorrhage and improved survival after severe liver injury in swine. Further studies are warranted.

Safety of New Phosphate Binders for Chronic Renal Failure

Phosphate (Pi) retention is a common problem in patients with chronic kidney disease, particularly in those who have reached end-stage renal disease (ESRD). In addition to causing secondary hyperparathyroidism and renal osteodystrophy, recent evidence suggests that, in ESRD patients, high serum phosphorus concentration and increased calcium and phosphorous (Ca x P) product are associated with vascular and cardiac calcifications and increased mortality. Dietary phosphorus restriction and Pi removal by dialysis are not sufficient to restore Pi homeostasis. Reduction of intestinal Pi absorption with the use of Pi binders is currently the primary treatment for Pi retention in patients with ESRD. The use of large doses of calcium-containing Pi binders along with calcitriol administration may contribute to over-suppression of parathyroid hormone secretion and adynamic bone disease as well as to a high incidence of vascular calcifications. When used in patients with impaired renal function, aluminium salts were found to accumulate in bone and other tissues, resulting in osteomalacia and encephalopathy.Sevelamer, an aluminium- and calcium-free Pi binder can reduce serum phosphorus concentration and is associated with a significantly lower incidence of hypercalcaemia, while maintaining the ability to suppress parathyroid hormone production. An additional benefit of sevelamer is its ability to lower low density lipoprotein-cholesterol and total cholesterol levels. Sevelamer attenuates the progression of vascular calcifications in haemodialysis patients, which may lead to lower mortality. The use of sevelamer in non-dialysed patients might aggravate metabolic acidosis, common in these patients. Several other calcium-free Pi binders are in development. Lanthanum carbonate has shown significant promise in clinical trials in ESRD patients. Magnesium salts do not offer a significant advantage over currently available Pi binders. Their use is restricted to patients receiving dialysis since excess magnesium must be removed by dialysis. Iron-based compounds have shown variable efficacy in short-term clinical trials in small numbers of haemodialysis patients. Mixed metal hydroxyl carbonate compounds have shown efficacy in animals but have not been studied in humans. Major safety issues include absorption of the metal component with possible tissue accumulation and toxicity.

Chitosan supplementation does not affect fat absorption in healthy males fed a high-fat diet, a pilot study

BACKGROUND

The use of dietary supplements, especially those for weight control, is increasing. Advertising claims for some of these supplements may give consumers unrealistic expectations. For example, it is claimed that the supplement chitosan can block the absorption of up to 120 g of dietary fat per day.

OBJECTIVE

To test the effect of a chitosan supplement used as directed, on the absorption of dietary fat.

DESIGN

Seven healthy male volunteers with average age 28, range 23-30, average body mass index (BMI) 26, range 23-31, maintained a high fat intake (>120 g/day) for 12 days. On days 6-9, chitosan was taken as directed by the manufacturer prior to meals and snacks and totaled 15 capsules or 5.25 g of chitosan daily. A charcoal marker was consumed on days 2, 6 and 10 to mark the baseline and supplement periods. All feces were collected on days 2-12, and were divided based on the appearance of charcoal in the feces. Fecal fat content corresponding to the four baseline and four chitosan-supplemented days was measured.

RESULTS

Average dietary fat intake did not differ between baseline (135+/-5 g), and chitosan (135+/-3 g) periods. Fecal fat excretion did not differ between the two periods (6.9+/-1.0 g/day baseline; 6.8+/-0.4 g/day chitosan). The fecal fat content as a percentage of fat consumed did not differ (5.1+/-0.7% baseline, 5.0+/-0.3% chitosan). Fecal mass did not differ (176+/-26 g/day baseline, 182+/-14 g/day chitosan).

CONCLUSION

Consumption of this chitosan supplement did not increase fecal fat content and therefore did not block fat absorption.

Chitosan: some pharmaceutical and biological aspects--an update

Chitosan, a natural polysaccharide, is being widely used as a pharmaceutical excipient. It is obtained by the partial deacetylation of chitin, the second most abundant natural polymer. Chitosan comprises a series of polymers varying in their degree of deacetylation, molecular weight, viscosity, pKa etc. The presence of a number of amino groups permit chitosan to chemically react with anionic systems, thereby resulting in alteration of physicochemical characteristics of such combinations. Chitosan has found wide applicability in conventional pharmaceutical devices as a potential formulation excipient, some of which include binding, disintegrating and tablet coating properties. The polymer has also been investigated as a potential adjuvant for swellable controlled drug delivery systems. Use of chitosan in novel drug delivery as mucoadhesive, gene and peptide drug administration via the oral route as well as its absorption enhancing effects have been explored by a number of researchers. Chitosan exhibits myriad biological actions, namely hypocholesterolemic, antimicrobial and wound healing properties. Low toxicity coupled with wide applicability makes it a promising candidate not only for the purpose of drug delivery for a host of drug moieties (antiinflammatories, peptides etc.) but also as a biologically active agent. It is the endeavour of the present review to provide an insight into the biological and pharmaceutical profile of chitosan. Various investigations carried out recently are reported, although references to research performed on chitosan prior to the recent reviews have also been included, where appropriate.

Cross-linking chitosan-Fe(III), an oral phosphate binder: studies in vitro and in vivo

The objective was to evaluate the in vitro and in vivo phosphate binding properties of cross-linked chitosan iron (III) (CH-Fe(III)-CL), a potential oral phosphate binder for treating hyperphosphatemia. At equilibrium, the in vitro phosphate binding of CH-Fe(III)-CL was 23.6 mg g(-1) for simulated gastrointestinal conditions. In hyperphosphatemic rats, CH-Fe(III)-CL was similar to iron sulfate in reducing serum phosphate by about 35%.

Chitosan induces apoptosis via caspase-3 activation in bladder tumor cells

Recently, because of its low toxicity and biological effects, chitosan has been widely used in the medical and pharmaceutical fields, e.g., for nasal or oral delivery of peptide or polar drug delivery. Here, we report a growth-inhibitory effect of chitosan on tumor cells. The growth inhibition was examined by WST-1 colorimetric assay and cell counting. We also observed DNA fragmentation, which is characteristic of apoptosis, and elevated caspase-3-like activity in chitosan-treated cancer cells. The findings suggest that chitosan may have potential value in cancer therapy.

Clinical and biochemical evaluation of chitosan for hypercholesterolemia and overweight control

After providing basic information on enzymes involved in cholesterol homeostasis, and on management of hypertriglyceremia and hypercholesterolemia, with the aid of cholestyramine and fibric acid, this chapter examines the effects of the ingestion of chitosan. Dietary chitosan is effective on serum cholesterol and in atherosclerosis in normal and diabetic mice, and lends itself to the treatment of hypercholesterolemia in humans. It also exhibits antiulcer, antiarthritic, antihypertension and antiuricemic properties. The published human trials, analysed statistically, further indicate that chitosan is effective to control overweight when associated to a diet. This chapter discusses several issues raised against the use of chitosan, namely, depletion of zinc and liposoluble vitamins, as well as advantages such as enhanced absorption of nutrients and competitive inhibition of lipases. It also directs attention to the unexplored areas of fungal and algal chitosans, and the use of chitins instead of chitosans.

Biochemistry, histology and clinical uses of chitins and chitosans in wound healing

Biodegradability, biocompatibility and capacity to promote the synthesis of hyaluronan are main characteristics of chitin-derived wound healing materials, whose biological significance in the human body depends largely on the actions that certain hydrolases exert on them. The resulting chitooligomers stimulate various cells, while the released monomers are phosphorylated and incorporated into hyaluronan, keratan sulphate and chondroitin sulphate, components of the intracellular matrix and connective tissue. The healing process favoured by these materials is examined in terms of macrophage activation, cytokine production by macrophages and fibroblasts, antiinflammatory action, angiogenesis stimulation, granulation and scar formation. Current biomedical applications are illustrated by the treatment of leg ulcers, the use of skin substitutes, and the regeneration of bone, nerve and meniscus tissues.

Effect of iron(III) chitosan intake on the reduction of serum phosphorus in rats

Because of the widespread use of aluminium- and calcium-containing phosphate binders for the control of hyperphosphataemia in patients with end-stage renal failure, an iron(III) chitosan complex was synthesised and fed to rats to measure its effect on serum phosphorus and calcium, intestinal phosphate binding and phosphate absorption. Thirty-six Wistar rats were randomly selected and distributed into a baseline group (n = 6), a control group (n = 8 (days 0-15), n = 8 (days 16-30)) and a treatment group (n = 8 (days 0-15), n = 8 (days 16-30)). The control groups ingested AIN-76 diet mix with a 1% w/w fibre content; however, the treatment groups had the fibre content completely substituted with iron(III) chitosan. The mean weights of the treated rats were slightly lower from 15 days (not significant); but overall, rat growth was not stunted in the treatment groups. The serum phosphorus levels of the treated group (n = 8) were significantly reduced after 15 days (P = 0.004; control: 5.7+/-0.9 mg dL(-1); treatment: 4.4+/-0.5 mg dL(-1); 95% CI of difference: 0.5-2.2) and 30 days (P = 0.002; control: 5.5+/-0.9 mg dL(-1); treatment = 4.1+/-06 mg dL(-1); 95% CI of difference: 0.6-2.3) as compared with the respective control group. The serum calcium-phosphorus product was 62.0+/-12.1 mg2 dL(-2) for the control and 45.1+/-6.6 mg2 dL(-2) for the treatment group after 30 days (P = 0.004). The serum iron concentration of the treatment group did not differ from the baseline value after 15 and 30 days, but the treatment group was significantly higher than the control group (P<0.05) after 30 days. The faeces phosphorus levels (mg day(-1)) were higher (P<0.01) and its iron content was much higher (P<0.01) for the treated group. The urine phosphorus (mg kg(-1)) was not significantly reduced for the treated group, but the mean was consistently less. The kidney and liver weights of both groups were similar, but the phosphorus content of the kidney (mg (g kidney)(-1)) was higher for the treated group after 30 days (P = 0.041; control, 4.2+/-1.2 mg g(-1) vs treatment, 5.6+/-1.4 mg g(-1). Because iron(III) chitosan had a high phosphorus-binding capacity of 308 (mg P) per gram of Fe3+ for both the in-vitro (pH 7.5) and in-vivo studies, which is greater than nearly all commonly used phosphate binders, and a small net phosphorus absorption difference of 3.7 mg day(-1), it is an efficient phosphate binder for lowering serum phosphate levels without increasing serum calcium levels.

Oral phosphate binders: phosphate binding capacity of iron (III) hydroxide complexes containing saccharides and their effect on the urinary excretion of calcium and phosphate in rats

Phosphate binders that contain aluminum or calcium are frequently prescribed to treat hyperphosphatemia in patients with end-stage renal disease (ESRD), but an accumulation of aluminum can lead to encephalopathy, aluminum-related bone disease (ARBD) such as osteomalacia, anaemia, and resistance to erythropoietin, and calcium accumulation can lead to hypercalcaemia. High phosphate concentrations are reduced in vitro and in vivo by a phosphate adsorption pill, which is synthesized by hydrolyzing ferrous sulfate in the presence of saccharides, to form an iron (III)-saccharide complex that is acid resistant and binds phosphate greater than iron (III) hydroxide alone. Under in vitro conditions, containing 3.26 mg P/dL, the iron (III)-sucrose complex showed the highest phosphate adsorption capacity at pH 2 with artificial gastric juice, 58.9 mg P/g binder. For the 7 day in vivo study, 0% (Group 1), 1% (Group 2), 4% (Group 3), and 8% (Group 4) iron (III)-sucrose complex was admixed into the rodent chow by weight and fed to 15 male Wistar rats. The weight and volume of the feces and urine, and the calcium, iron, and phosphorus excretions in the feces and urine samples were monitored for any signs of irregularity. Total urine outflow was collected during a 24-h period to determine the amount of phosphate recovered, which indicates the ability of the phosphate binder to reduce gastrointestinal phosphate absorption. The fecal iron excretion was significantly effected by the amount of binder ingested throughout the study for Group 2 (p < 0.001), Group 3 (p < 0.01), and Group 4 (p < 0.001). The urinary calcium excretion (mg/rat/24-h) significantly increased by the 7th day for Group 2 (p < 0.05) and Group 4 (p < 0.01) in comparison to the control. Finally, after 7 days, there was a significant drop in the urinary phosphorus levels (mg P/rat/24-h) in a dose dependent manner for Group 2: from 7.82 +/- 1.46 to 1.98 +/- 0.10 mg P/rat/24-h (102 mg P/dL/24-h; p < 0.05); Group 3: from 6.70 +/- 1.14 to 0.16 +/- 0.09 mg P/rat/24-h (6.0 mg P/dL/24-h; p < 0.01); and Group 4: from 8.25 +/- 0.67 to 0.04 +/- 0.01 mg P/rat/24-h (0.9 mg P/dL/24-h; p < 0.01). The results show that this new adsorbent might provide an alternative to conventional aluminum and calcium containing phosphate-binding agents for combating hyperphosphataemia.