Hesperetin treatment attenuates glycation of lens proteins and advanced­glycation end products generation.

Advanced glycation end products (AGEs) in lens proteins increase with aging, thus inducing cataracts and/or presbyopia. Hesperetin (Hst), which is an abundant plant flavanone largely derived from citrus species, and its derivatives attenuate cataracts and presbyopia in vivo and in vitro; however, no reports have described its effects on AGE formation in lens proteins. The present study demonstrated that AGEs in lens proteins increase with age in mice. Additionally, it showed that Hst can prevent AGEs and N(ε)­carboxymethyl­lysine generation and modification of lens proteins using in vitro in human lens epithelial cell lines and ex vivo in mouse lens organ cultures. Furthermore, treatment with Hst prevented lens hardening and decreased chaperone activity in lens proteins. These results suggested that Hst and its derivatives are good candidates for the prevention of presbyopia and cataracts.

Identification of a Novel Oligosaccharide in Maple Syrup as a Potential Alternative Saccharide for Diabetes Mellitus Patients.

The incidence of diabetes mellitus (DM) is increasing rapidly and is associated with changes in dietary habits. Although restrictions in the use of sweeteners may prevent the development of DM, this might reduce the quality of life of patients with DM. Therefore, there has been a great deal of research into alternative sweeteners. In the search for such sweeteners, we analyzed the carbohydrate content of maple syrup and identified a novel oligosaccharide composed of fructose and glucose, linked at the C-4 of glucose and the C-6 of fructose. This oligosaccharide inhibited the release of fructose from sucrose by invertase (IC50: 1.17 mmol/L) and the decomposition of maltose by α-(1-4) glucosidase (IC50: 1.72 mmol/L). In addition, when orally administered together with sucrose to rats with DM, the subsequent plasma glucose concentrations were significantly lower than if the rats had been administered sucrose alone, without having any effect on the insulin concentration. These findings suggest that this novel oligosaccharide might represent a useful alternative sweetener for inclusion in the diet of patients with DM and may also have therapeutic benefits.

[Effect of Methylcellulose (Cellulose Derivatives) on Ibuprofen-crushing Efficiency in Nano Pulverizer NP-100].

It is expected that drug systems using nanoparticles will improve the problem of poor water solubility and bioavailability of lipophilic drugs. However, it is difficult to prepare the formulations containing nanoparticles, and it is important to determine the concentration and kind of additives to prepare the formulations. We previously reported that a nano pulverizer NP-100 is possible to prepare drug nanoparticles for the 2-3 min, and the cellulose derivatives (metolose®, methylcellulose) is usefulness to prepare the nanoparticles by the mill method. In this study, we investigated the relationships of methylcellulose type and crushing efficiency in NP-100. First, we demonstrated the effect of viscosity in the various methylcellulose on the ibuprofen (IBU, lipophilic drug) particle size, and showed that the viscosity did not relate the crushing efficiency by the NP-100. Next, we measured the changes of cumulative size frequency curve in IBU particles by the combination of the NP-100 and 0.1-2.0% methylcellulose (SM-4, 400 and 4000). The appropriate addition reached IBU nanoparticles, although, the appropriate addition amount of methylcellulose was different in the SM-4 (0.5%), 400 (1.0%) and 4000 (1.2%). In addition, the IBU became meringue-like when subjected to the bead mill method in the less of methylcellulose, and excessive addition of methylcellulose increased the ratio of coarse particle. In conclusion, this results show that the appropriate addition amount of methylcellulose is different in the type of methylcellulose, and these changes of cumulative size frequency curve is useful as index to determine the concentration and type of additives in the nanoparticle production.

Co-administration of Magnesium Ion Prevents Indomethacin-Induced Intestinal Ulcerogenic Lesions in Adjuvant-Induced Arthritis Rats.

In a study to find ways to prevent the side effects of indomethacin (IMC), we previously reported that magnesium ion (Mg2+) can prevent the onset of IMC-induced gastric mucosa in adjuvant-induced arthritis (AA) rats, a model for rheumatoid arthritis (RA). In this study we investigated whether the co-administration of IMC and Mg2+ prevents the formation and aggravation of intestinal ulcerogenic lesions in AA rats. The single oral administration of an excessive dose of IMC (40 mg/kg) induces hemorrhagic lesions and nitric oxide (NO) production via inducible nitric oxide synthase (iNOS) in the jejunal and ileal mucosa of AA rats, and the extent of the lesions, as well as iNOS and NO levels in AA rats are higher than in normal rats. On the other hand, the co-administration of 200 mg/kg Mg2+ attenuates intestinal ulceration and the elevation in the iNOS and NO levels in AA rats. Further, hemorrhagic lesioning and enhanced iNOS and NO levels in AA rats also result from the repetitive oral administration of 3 mg/kg IMC (therapeutic dose) for 42 d (once a day), and these changes are also prevented by the co-administration of 200 mg/kg Mg2+. In conclusion, the co-administration of Mg2+ suppresses the ulcerogenic response to IMC in the jejunal and ileal mucosa of AA rats, probably by preventing the elevation of iNOS and NO levels in the region.

Pharmacokinetic Studies of Gel System Containing Ibuprofen Solid Nanoparticles.

In the therapy of rheumatoid arthritis, ibuprofen (IBU) is widely used; however, it has been limited the clinical use by its systemic side effect, such as gastrointestinal lesions. Therefore, we prepared topical gel ointment used IBU solid nanoparticles (IBUnano-gel formulation). In addition, we demonstrated their anti-inflammatory effect by using arthritis model rat (adjuvant-induced arthritis rat, AA rat). The gel formulations were prepared using additives (Carbopol 934, 2-hydroxypropyl-ß-cyclodextrin and methylcellulose) and bead mill-method. The IBU particle size in the IBUnano-gel formulation was 208 nm. The increase in inflammation of the hind feet of AA rats was attenuated by the treatment with the IBUnano-gel formulation, and preventive effect was higher than that of a gel formulation containing IBUmicroparticles (IBUmicro-gel formulation, mean particle size 85.4 µm); the accumulation and permeability through the skin of IBU from the IBUnano-gel formulation were significantly larger in comparison with the IBUmicro-gel formulation. Further, no gastrointestinal lesions were observed in AA rats following the repetitive administration of the 5% IBUnano-gel formulation (0.30 g) for 42 days (once a day). These results suggest that the dermal application of IBU-nanoparticles provide effective and efficient therapy that spares patients from unwanted side effects.

Phloridzin-sensitive transport of echinacoside and acteoside and altered intestinal absorption route after application of Cistanche tubulosa extract.

OBJECTIVES: The objective of this study was to address the beneficial effects of Cistanche tubulosa extract on improving the low intestinal permeability of echinacoside (ECH) and acteoside (ACT). METHODS: Absorption of ECH and ACT in C. tubulosa extract was characterized using human intestinal Caco-2 cell monolayers with intact compounds. Glucose transporter-dependent absorption of ECH and ACT was confirmed by an in-situ intestinal perfusion technique. KEY FINDINGS: The apparent permeability (Papp ) was not significantly different between intact ECH and intact ACT. In the presence of phloridzin, the Pap p of the ECH and ACT at a high dose was reduced to 20% of the respective non-treatment, but was not altered by phloretin and verapamil. C. tubulosa extract at low and high doses enhanced the Papp of ECH and ACT (both by threefold), resulting in their large participation in sodium-dependent glucose transporter-independent absorption. At a low concentration, concomitant ECH and ACT levels in portal blood were significantly suppressed by phloridzin. CONCLUSION: The dietary and medicinal C. tubulosa extract enhancing the intestinal absorption of ECH and ACT may serve to better manage human health, although the involvement of phloridzin-sensitive transport should be reduced.

Effect of magnesium ion supplementation on obesity and diabetes mellitus in Otsuka Long-Evans Tokushima Fatty (OLETF) rats under excessive food intake.

Several epidemiologic studies have found that magnesium ion (Mg²âº) is related to obesity and type 2 diabetes mellitus. However, there have been almost no reports on the effects of a combination of excessive food intake and Mg²âº supplementation on metabolic syndrome and various blood tests values for diabetes mellitus. In this study, we investigated changes in body weight and blood test values for diabetes mellitus of Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model for human type 2 diabetes mellitus via metabolic syndrome, under conditions of combined excessive food intake and Mg²âº supplementation. The rats received Mg²âº supplementation by drinking magnesium water (Mg²âº; 200 mg/l). No significant differences were observed in the levels of food or water intake between OLETF rats drinking purified water (PW) or magnesium water (MW). Type 2 diabetes mellitus with metabolic syndrome developed at 30 weeks of age, and the body weights and plasma insulin levels of OLETF rats at 60 weeks of age were lower than those of normal rats. The plasma glucose (PG) levels in 38-week-old OLETF rats drinking MW were significantly lower than in those of rats drinking PW, while the body weights and the levels of triglycerides (TG) and insulin of 38-week-old MW-drinking OLETF rats were significantly higher than those of their PW-drinking counterparts. On the other hand, the decreases in body weight and insulin levels in 60-week-old OLETF rats were suppressed by MW supplementation. The present study demonstrates that Mg²âº supplementation delays the development of diabetes mellitus in OLETF rats under conditions of excessive food intake. In addition, obesity and high blood TG levels were observed in OLETF rats receiving Mg²âº supplementation in conjunction with excessive food intake.

Co-administration of water containing magnesium ion prevents loxoprofen-induced lesions in gastric mucosa of adjuvant-induced arthritis rat.

Non-steroidal anti-inflammatory drugs (NSAIDs) comprise one of the most frequently used classes of medicines in the world; however, NSAIDs have significant side effects, such as gastroenteropathy, and rheumatoid arthritis patients taking NSAIDs are more susceptible to NSAID-induced gastric lesions as compared to patients with other diseases. In Asian countries, loxoprofen has been used clinically for many years as a standard NSAID. We demonstrate the preventive effect of the co-administration of water containing magnesium ion (magnesium water, 1-200 µg/kg) on the ulcerogenic response to loxoprofen in adjuvant-induced arthritis (AA) rats. Oral administration of loxoprofen (100 mg/kg) caused hemorrhagic lesions in the gastric mucosa of AA rats 14 d after adjuvant injection, and, following loxoprofen administration, the lesion score of AA rats was significantly higher than that of normal rats. The expression of inducible nitric oxide synthase (iNOS) mRNA and nitric oxide (NO) production in the gastric mucosa of AA rats were also increased by the administration of loxoprofen, and the increase in lesions and NO were prevented by the administration of aminoguanidine, an iNOS inhibitor. The co-administration of magnesium water decreased the ulcerogenic response to loxoprofen in AA rats. In addition, the co-administration of magnesium water attenuated the increase in iNOS mRNA expression and NO production in AA rats receiving loxoprofen. These results suggest that the oral co-administration of magnesium water to AA rats has a potent preventive effect on the ulcerogenic response to loxoprofen, probably by inhibiting the rise in iNOS and NO levels in the gastric mucosa.

Preparation of ophthalmic formulations containing cilostazol as an anti-glaucoma agent and improvement in its permeability through the rabbit cornea.

To evaluate the pharmacological properties of cilostazol (CLZ), we examined its intraocular pressure (IOP) -lowering effect. CLZ is an inhibitor of Type III phosphodiesterase that increases intracellular cyclic AMP levels by restraining platelet aggregation, and has a potential protective effect against atherosclerosis. We attempted to apply it for use as an anti-glaucoma agent; however, the application of CLZ in the ophthalmic field is limited due to its poor water solubility. We attempted to enhance CLZ solubility using 2-hydroxypropyl-beta-cyclodextrin (HPbetaCD). The solubility of CLZ increased with increasing HPbetaCD concentrations, and 0.05% CLZ was dissolved in 10% HPbetaCD. Moreover, fine particle suspension of 0.5% CLZ in 5% HPbetaCD (soluble CLZ: ca. 0.027%) were prepared using a Microfluidizer, an impact-type emulsifying comminution device. In an in vitro transcorneal penetration experiment through the rabbit cornea, the CLZ penetration rate was dependent on the CLZ content of the solutions and suspensions. When a 0.05% CLZ ophthalmic solution was instilled into a rabbit eye, the absorption rate constant for CLZ into an aqueous humor was 0.0059+/-0.001 min(-1), and the elimination rate constant was 0.048+/-0.024 min(-1). Also CLZ ophthalmic solutions and fine particle suspension were examined to for their ability to reduce enhanced intraocular pressure (IOP) of rabbits in a darkroom. The instillation of 0.05% CLZ ophthalmic solutions and 0.5% CLZ fine particle suspensions into rabbit eyes reduced the enhanced IOP. These results demonstrate that the instillation of CLZ ophthalmic solutions and fine particle suspensions may represent an effective anti-glaucoma formulation.

Preventive effect of co-administration of water containing magnesium ion on indomethacin induced lesions of gastric mucosa in adjuvant-induced arthritis rat.

It is well known that nonsteroidal anti-inflammatory drugs (NSAIDs) have significant side effects, such as gastroenteropathy, and that rheumatoid arthritis patients taking NSAIDs are more susceptible to NSAIDs-induced gastric lesions as compared with patients with other diseases. We demonstrate the preventive effect of the co-administration of bittern water (BW, nigari-sui in Japanese), which enables the effective intake of Mg(2+), on the ulcerogenic response to indomethacin in adjuvant-induced arthritis (AA) rats. Four kinds of BW with different Mg(2+) contents; ranging from 10-200 mg/l Mg(2+) (BW-10, 25, 50, 200) were used in this study. Arthritis was induced by the injection of 50 microl of a suspension of 10 mg/ml heat-killed butyricum (Mycobacterium butyricum) in Bayol F oil into the plantar region of the right hind foot and tail of rats. Oral administration of indomethacin (40 mg/kg) caused hemorrhagic lesions in the gastric mucosa of AA rats at 14 d after adjuvant injection, and the lesion score of AA rats administered indomethacin was significantly higher than that of normal rats administered indomethacin. The expression of the mRNA for inducible nitric oxide synthase (iNOS) mRNA expression and the production of nitric oxide (NO) in the gastric mucosa of AA rats were also increased by the administration of indomethacin. The co-administration of BWs decreased the ulcerogenic response to indomethacin in AA rats. In addition, the administration of BW attenuated the increase in iNOS mRNA expression and NO production in AA rats receiving indomethacin. The oral administration of Mg(2+) to AA rats had a potent preventive effect on the ulcerogenic response to indomethacin in AA rats, probably due to an inhibition in the rise in iNOS and NO levels in the gastric mucosa.

Preventive effect of water containing magnesium ion on paw edema in adjuvant-induced arthritis rat.

We demonstrate the preventive effect of bittern water (BW), which enables the effective intake of magnesium ion (Mg(2+)), on paw edema in adjuvant-induced arthritis (AA) rat. BW (five kinds; BW-1, 2, 3, 4, 5) containing 10-200 mg/l Mg(2+) was used in this study. Arthritis was induced by the injection of 50 microl of a suspension of 10 mg/ml heat-killed butyricum (Mycobacterium butyricum) in Bayol F oil into the plantar region of the right hind foot and tail of rats. Paw edema of the right and left hind feet of AA rats were reduced by the administration of BW for 14 d after adjuvant injection in comparison with those of AA rats administered purified water. The preventive effect increased with the increasing Mg(2+) content of the BW. In addition, a combination of indomethacin (IM, 2 mg/kg) and BW-5 (200 mg/l Mg(2+)) prevented paw edema of the right and left hind feet of AA rats in comparison with IM alone. The fate of plasma IM after the oral administration of the combined IM (2 mg/kg/d) and BW-5 was similar to that after the administration of IM alone. In conclusion, the oral administration of Mg(2+) to AA rats potently prevents the development of inflammation, and the combination of IM and Mg(2+) may provide an effective therapy of arthritic edema.

Delay of cataract development in the Shumiya cataract rat by the administration of drinking water containing high concentration of magnesium ion.

We discovered that the cataract development in the Shumiya cataract rat (SCR) can be prevented by the administration of deep-sea drinking water (DDW). A standard diet based on the American Institute of Nutrition guidelines (AIN-76) and DDW containing a high mineral concentration such as low, medium and high Mg2+ content (50, 200 and 1000 mg of Mg2+/l, respectively) were used in this study. SCRs were freely fed with combinations of the standard diet and purified water or DDW during 5-15 weeks of age. The opacities of SCR lenses were documented by anterior eye segment analysis system EAS-1000. The onset of opacification of cataractous SCR lenses administered a combination of standard diet and purified water started at 11 weeks of age, and mature cataracts had formed at 13 weeks of age. However, the supplementation of Mg2+ by administration with medium DDW showed the greatest effect of delay of cataract onset in SCR. In addition, even cataractous SCR lenses at 14 weeks of age showed differences in opacity level. The opacification and Ca2+ of the lenses in cataractous SCR administered medium DDW were lower than those administered purified water. In conclusion, the present study demonstrates that administration of DDW potently delays cataract development in SCR, and this may be caused by inhibiting the increase in Ca2+ levels in the lens.

Effects of magnesium content in the feed on cataract development in Shumiya cataract rat.

Cataract is a phenomenon in which the eye becomes opaque resulting in severe visual impairment, and senile cataract is the most common cause of blindness in the world. We investigated the effect of magnesium (Mg) supplementation on cataract development using shumiya cataract rat (SCR). The SCR were fed on either a low Mg (Mg 50 mg/kg), standard Mg (Mg 500 mg/kg), or high Mg (Mg 5000 mg/kg) diet from aged 5 to 15 weeks. The growth curve of SCRs fed on a low Mg diet was the same as that of SCRs fed on a standard diet. The growth curve of SCRs fed on a high Mg diet was significantly suppressed in comparison with those fed on a standard diet. The opacification of lenses from SCR fed on a standard Mg diet started at 11 weeks of age. The opacification of lenses from SCR fed on a high Mg diet was similar to that from SCR fed on a standard Mg diet. On the other hand, the low Mg diet accelerated the onset of cataract development, and the opacity started at 10 weeks of age. In addition, the calcium ion (Ca2+) content in SCR lenses fed on a low Mg diet significantly increased in comparison with that in lenses from SCR fed on a standard Mg diet. These results suggest that Mg deficiency causes acceleration of cataract development in SCR, probably due to a rise in the Ca2+ content in the lens.