Effect of a polyglucosamine on the body weight of male rats: Mechanisms of action

A Randomized Double-Blind Placebo-Controlled Clinical Study to Evaluate the Effect on the Weight of a Medical Device with Polyglucosamine L112 in a Group of Overweight and Obese Subjects

BACKGROUND

Overweight and obesity have reached epidemic proportions and safe treatments are needed to heal these diseases.

OBJECTIVE

The objective of this study is to examine the activity of a medical device based on polyglucosamine polymers (PG) on body weight (BW) reduction, insulin resistance, and the serum levels of fat-soluble vitamins and glucosamine.

METHODS

A double-blind placebo-controlled interventional study comparing PG and a placebo (PL) was conducted. One hundred and fifty overweight or obese cases were treated, divided into two groups for a period of 90 days at the dosage of 3 g/day.

RESULTS

One hundred and nineteen cases (58 with PG and 61 with PL, respectively) concluded the treatment. PG was more effective than the PL on the reduction of BW and insulin resistance. No modification of fat-soluble vitamins (Vit A, E, D3, K1) and glucosamine levels was shown. Total cholesterol levels were significantly more reduced in the PG group compared to the PL group as it was for subjects with a BW decrease of >5%.

CONCLUSIONS

PG acts as a safe medical device, is not absorbed, and binds lipids in the upper gastrointestinal tract, reducing their availability, with a significant activity on the reduction of BW, insulin resistance, and cholesterol levels without the modification of fat-soluble vitamins.

Randomised, double-blind, clinical investigation to compare orlistat 60 milligram and a customized polyglucosamine, two treatment methods for the management of overweight and obesity

BACKGROUND

The efficacy of a non-prescription drug to support weight loss programs has yet to be compared. This clinical trial investigates the comparability of orlistat 60 milligram (mg) and polyglucosamine.

METHODS

Sixty-four overweight or obese subjects were included in a two-center double-blind study. One center was in Germany [center 1] and the other was in Italy [center 2]. The subjects (26 in center 1 and 38 in center 2) were recommended to follow a calorie deficit of about 2000 kilojoules/day and to increase their physical activity to 3 metabolic equivalent hours (MET h)/day. In both centers, subjects were randomized to receive polyglucosamine (2 tablets x 2) or orlistat (1 capsule x 3) for a period of 12 weeks. Weight loss was considered as a main variable together with the reduction of 5 per cent (%) of body weight (5R). Body Mass Index (BMI) and waist circumference (WC) were taken as secondary variables.

RESULTS

A significant difference in weight loss between the two groups was shown, 6.7 ± 3.14 kilogram (kg) in group polyglucosamine versus 4.8 ± 2.24 kg in group orlistat (t test p < 0.05) respectively; BMI and WC reduction were also more consistent with polyglucosamine treatment than with orlistat treatment (t test p < 0.05). No significant difference was found in the number of subjects who achieved 5R (70% for polyglucosamine and 55% for orlistat group; chi square p > 0.05). The administration of polyglucosamine following energy restriction and increase in physical activity reduces body weight, BMI and WC more efficiently than orlistat.

CONCLUSIONS

Even though both groups were instructed to adopt a calorie restricted diet together with increased physical activity an additional weight loss in the polyglucosamine group of 1.6 kilogram (kg) compared to the orlistat group (6.2 ± 3.46 versus 4.6 ± 2.36 kg) in both centers was seen despite the higher consumption of carbohydrates in Italy (center 2). A typical Italian diet is usually high in carbohydrate content whereas Germans tend to consume meals with higher fat content. This leads to the assumption that polyglucosamine limits both fat and carbohydrate absorption which would explain the comparable effective weight reduction in the Italian participants.

TRIAL REGISTRATION

Trial registration at ClinicalTrials.gov NCT02529631, registered on Aug 19, 2015 retrospectively registered.

Chitosan dosage regimen to trap fecal oil excretion after peroral lipase inhibitor administration in mice

This study was designed to investigate the oil entrapment and systemic oil absorption-reducing activities of chitosan. High-molecular-weight chitosan formed gel aggregates with oil and bile salts in vitro. The oil/chitosan ratio and the molecular weight of chitosan were optimized for the in vivo study, and a molecular weight >100,000 was effective in reducing the oil contamination of mouse fur. The oil/chitosan weight ratio required for effective oil entrapment was less than 13 and 5 in the in vitro and in vivo experiments, respectively. Chitosan administration was most effective during meals, and high-molecular-weight chitosan could trap and facilitate the reduction of systemic absorption of oil droplets separated by orlistat. The activity of the lipase inhibitor was not altered by chitosan as evidenced by thin layer chromatography, and orlistat was not absorbed systemically by the co-administration of chitosan.

Efficacy of polyglucosamine for weight loss-confirmed in a randomized double-blind, placebo-controlled clinical investigation

BACKGROUND

The purpose of this clinical study was to ascertain whether low molecular weight chitosan polyglucosamine is able to produce significantly better weight loss than placebo.

METHOD

115 participants were included in the study. We used a two-center randomized, double blind, placebo-controlled design. The participants followed a standard treatment (ST), which included the combination of a low-calorie diet achieved through creating a daily calorie deficit (500 cal) and an increased daily physical activity (7 MET-h/week). They were randomized to receive standard treatment plus placebo (ST + PL) or standard treatment plus polyglucosamine (ST + PG), respectively. Participants were instructed to take 2 × 2 tablets before the two meals containing the highest fat content for at least 24 weeks. Body weight, BMI, waist circumference and the time needed for a 5 % body weight reduction (5R) were taken as main variables.

RESULTS

The average weight loss over a period of 25 weeks in the ITT population was 5.8 ± 4.09 kg in the ST + PG group versus 4.0 ± 2.94 kg in the ST + PL (pU = 0.023; pt = 0.010). After 25 weeks, 34 participants achieved 5R in the ST + PG group (64.1 %) compared to only 23 participants in the ST + PL group (42.6 %) (ITT) (p Fisher = 0.033). Weight loss through hypo-caloric diets have been found to be effective. The additional effect of PG in combination with standard treatment is able to produce significantly better weight loss than placebo.

CONCLUSIONS

Participants treated with ST + PG showed a significant amount of weight loss, an additional 1.8 kg, compared to controls treated with ST + PL.

TRIAL REGISTRATION

Trial Registration at ClinicalTrials.gov: NCT02410785 Registered 07 April 2015.

Efecto de la administración subcrónica de glucosamina oral en la regulación del peso corporal, glucemia y dislipidemias provocada por una dieta hipercalórica en rata Wistar

Objetivo: Este estudio evaluó el efecto de la glucosamina oral en el sobrepeso y dislipidemia provocada por una dieta hipercalórica en ratas.Métodos: En 4 grupos de ratas Wistar: alimentados con dieta comercial para roedores y agua de beber sin grupo de control y con glucosamina (500 mg/kg-1 por día) grupo glucosamina y con dieta hipercalórica enriquecida al 24% (g/g) compuesta por manteca de cerdo y agua de beber sin grupo hipercalórico y con glucosamina grupo hipercalórico + grupo glucosamina, durante 22 semanas, se evaluaron el peso corporal, grasa abdominal, niveles de glucemia, triglicéridos, colesterol total y lipoproteínas de alta densidad en suero.Resultados: Se observó un aumento del peso corporal y glucemia en suero con dislipidemias en el grupo con dieta hipercalórica grupo hipercalórico versusgrupo de controle (p<0.001); al administrarse glucosamina para esta misma dieta grupo hipercalórico + grupo glucosamina se minimizaron los efectos presentados, disminuyendo la cantidad de grasa abdominal y los niveles del perfil lípido en suero (p>0.05) y regulándose el peso corporal, las lipoproteínas de alta densidad y la glucemia basal (p<0.05).Conclusion: La glucosamina reguló el peso corporal y la glucemia en sangre y minimizó las dislipidemias provocadas por la dieta hipercalórica, favoreciendo el aumento de colesterol lipoproteínas de alta densidad en las ratas. No afectó el peso corporal y el metabolismo lipídico cuando se administró con dieta comercial.

The effect of chitosan on the concentration of 17β-estradiol and free triiodothyronine in mice exposed to polychlorinated biphenyls (PCBs)

The aim of this work was to examine (i) how the applied PCB mixture influences the level of 17β-estradiol (E2) and free triiodothyronine (FT3) in the blood plasma of mice (C57/BL/6J) and (ii) whether supplementation with chitosan would protect against the observed changes in the examined plasma hormone concentrations. In the study we used a mixture of indicator PCBs (CB no. 28, 52, 101, 118, 138, 153, 180) and our results showed their anti-estrogenic effects. Exposure to the mixture resulted in a significant decrease (P < 0.05) in plasma concentration of E2 relative to the control, and chitosan administration did not prevent the decrease. To the contrary, E2 concentration in the blood plasma of the mice which received both the PCB mixture and chitosan was lower compared to those which did not receive chitosan. Exposure to the PCBs also resulted in a decrease in FT3 concentration in the treatedgroup, although it was not as pronounced as for E2 and was prevented with dietary supplementation with chitosan, with the observed FT3 level in the chitosan-treated group similar to the control. In summary, supplementation with chitosan can only to a certain extent minimize the negative effects of exposure to PCBs.

Blood contact properties of ascorbyl chitosan

Ascorbyl chitosan was synthesized by heating chitosan with ascorbic acid in isopropanol. The products were characterized by FTIR and C-13 NMR spectroscopies, SEM, and elemental analysis. Blood contact properties of ascorbyl chitosans were evaluated. The ascorbyl chitosans demonstrated to have increased lipid-lowering activity in comparison to chitosan alone upon contact with human blood serum in in vitro conditions. Furthermore, the total cholesterol/HDL ratio was improved towards the desirable ideal values after three hours contact with ascorbyl chitosan samples. The lipid-lowering activity increased with ascorbyl substitution. The inherent nonspecific adsorption capability of chitosan due to its chelating power with several different functional groups was exhibited by ascorbyl chitosans as well. This behavior was exemplified in a simultaneous decrease in the total iron values of the volunteers together with lower lipid levels. Furthermore, ascorbyl chitosans were observed to have less hemocompatibility but increased anticoagulant activity when compared to chitosan alone. Additional in vivo studies are necessary to support these results and to investigate further the advantages and disadvantages of these materials to prove their safety prior to clinical applications.