Dietary Patterns and Muscle Mass, Muscle Strength, and Physical Performance in the Elderly: A 3-Year Cohort Study

OBJECTIVES

Nutritional support effectively prevents and treats sarcopenia; however, the influence of overall dietary patterns on sarcopenia parameters is less investigated. This study aimed to determine the association between adherence to Mediterranean-style diet (MD), Dietary Approaches to Stop Hypertension (DASH), Japanese Food Guide Spinning Top (JFG-ST), and modified JFG-ST (mJFG-ST) and muscle mass, muscle strength, and physical performance in community-dwelling Japanese elderly.

DESIGN AND SETTINGS

This prospective cohort study recruited individuals aged over 60 years from a community college in Nagoya, Japan.

PARTICIPANTS AND MEASUREMENTS

A total of 666 participants were followed up annually from 2014 to 2017. Demographic data, anthropometric measurements, and sarcopenia parameters including walking speed (WS), hand grip strength in the dominant hand (HGS), and skeletal mass index (SMI) were recorded. Self-recall dietary intake was assessed using a validated food frequency questionnaire comprising 29 food groups. Adherence to MD, DASH, JFG-ST, and mJFG-ST was determined by tertiles.

RESULTS

At baseline, the mean age of all participants (56.5% women) was 69.4±4.4 years. WS, HGS, and SMI were 1.4±0.2 (m/s), 28.9±8.1 (kg), and 6.7±1.0 (kg/m2), respectively. In longitudinal analysis, participants with higher JFG-ST adherence scores were more likely to have higher SMI (Q3 vs. Q1: mean difference, 0.048; p=0.04) after adjustment, and its benefits were more evident in men (Q2 vs. Q1: mean difference, 0.098; p=0.047; Q3 vs. Q1: mean difference, 0.091; p=0.017) than in women. WS and HGS were not associated with any type of dietary pattern.

CONCLUSIONS

Adherence to JFG-ST was positively associated with SMI in Japanese community-dwelling elderly adults aged over 60 years, specifically in men. The country-specific dietary recommendations are required to be developed for sarcopenia prevention.

Structure-activity relationships of saponins and cardiac glycosides. III. Beta-L-xylopyranosyl-(1-->6)-alpha- and -beta-D-glucopyranosides

Comparisons of the biological activities of diosgenyl, methyl glycyrrhetinate or digitoxigenyl 3-O-beta-L-xylopyranosyl-(1-->6)-beta-D-glucopyranoside with those of other previously tested glycosides confirmed our assumption that both the hemolytic and antifungal activities of steroid saponins are generally parallel to each other, while almost all hemolytic triterpenoid saponins and nonhemolytic ones have no antifungal activity, and that cardiac diglycosides having a (1-->4) sugar linkage have stronger activities than those with a (1-->6) or a (1-->2) linkage. On the other hand, the case of the diosgenyl 3-O-beta-L-xylopyranosyl-(1-->6)-alpha-D-glucopyranoside didn't conform to the above assumption, but those of methyl glycyrrhetinate and digitoxigenyl did.

Biological activities of synthetic triterpenoid and steroid beta-D-glucopyranosyl-(1-->2)-alpha-D-glucopyranosides

Comparisons of the biological activities of diosgenyl, methyl glycyrrhetinate, or digitoxigenyl 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-D-glucopyranoside with those of other previously tested glycosides confirmed our assumption that both haemolytic and antifungal activities of steroid saponins are generally parallel to each other, while almost all haemolytic triterpenoid saponins have no antifungal activity. The earlier supposition that cardiac diglycosides having a (1-->4) sugar linkage have stronger activities than those with a (1-->6) linkage has been extended by the demonstration of reduced activity also in those with a (1-->2) linkage.

Biological activities of synthetic triterpenoid and steroid beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranosides

Comparisons of the activities of diosgenyl, methyl glycyrrhetinate or digitoxigenyl 3-O-beta-D-xylopyranosyl-(1-->6)-beta-D-glucopyranoside with those of our previous glycosides supported our assumptions that both haemolytic and antifungal activities of steroid saponins are generally parallel to each other, while almost all haemolytic triterpenoid saponins show no antifungal activity, and that both antiviral and anti-ATPase activities of cardiac glycosides having a (1-->6) sugar linkage are much lower than those of the others.

Structure-activity relationships of synthetic saponins

The haemolytic and antifungal activities of synthetic diosgenyl, tigogenyl, hecogenyl, methyl oleanolate, methyl ursolate and methyl glycyrrhetinate glycosides were compared with each other. Both activities of the steroid glycosides were generally parallel to each other, while almost all haemolytic triterpenoid glycosides showed no antifungal activity.

Structure-activity relationships of synthetic cardiac glycosides

The antiviral, cytotoxic and anti-ATPase activities of 14 synthetic bufalyl glycosides were compared with each other. Among these glycosides, the activities of the gentiobioside and the melibioside were much weaker than those of the others. On the other hand, these three activities were found to be highly correlated with each other. These were parallel to the case of the digitoxigenyl glycosides in our previous paper.

Production of an anti-allergic triterpene bryonolic acid, by plant cell cultures

Cell suspension cultures of Luffa cylindrica, Citrullus lanatus, and related cucurbitaceous plants accumulate large quantities of bryonolic acid (3 beta-hydroxy-D:C-friedoolean-8-en-29-oic acid) [1], an acidic, pentacyclic triterpene found exclusively in the roots of the intact plants. This compound could readily be isolated from cultured cells with CHCl3 and purified simply by recrystallization. Pharmacological tests using mice demonstrated that bryonolic acid or its derivative is active against at least three types of allergies and that its activity could be increased significantly by preparing synthetic derivatives, in particular a potassium salt of its succinate ester. The biosynthesis of bryonolic acid from mevalonic acid via isomultiflorenol has been elucidated by tracer and enzymological experiments using cultured cells of watermelon both in vitro and in vivo. Furthermore, cell fractionation and electron microscopic studies on subcellular structures of luffa cells suggested that minute vesicles originating from elongated, rough endoplasmic reticulum probably play an important role in the transport of bryonolic acid which largely accumulates in the cell wall of cultured cells. The results obtained from the present study indicate that plant cell culture would be useful not only as a biological system for elucidating biosynthetic mechanisms but also as a potential source of new pharmacologically active compounds.

Activity of thyroid stimulating antibody and thyroid stimulation blocking antibody determined by radioiodine uptake into FRTL-5 cells

To investigate the pathophysiology of patients with autoimmune thyroid diseases, we measured serum thyroid stimulating antibody (TSAb) activity and thyroid stimulation blocking antibody (TSBAb) activity by determining the radioiodine (125I) uptake into FRTL-5 cells. FRTL-5 cells were pre-incubated for seven days with 5H medium and then incubated for 48 hours with patients' crude IgG prepared by polyethylene glycol precipitation. In order to measure TSBAb, 10 microU/ml TSH was also added. 125I was added one hour before the end of the 48 hour incubation period. After the incubation, the medium was aspirated, and the radioactivity in the cells was counted. In patients with untreated hyperthyroid Graves' disease, TSAb was detectable in 18 of 20 patients, the detectability being 90%, and activity showed a statistically significant positive correlation with TSAb activity determined by c-AMP accumulation. Out of 41 patients with hypothyroidism, TSBAb determined by 125I uptake was positive in six cases, the detectability being 14.6%. The inhibition of 125I uptake by one of these six IgGs was suggested to be at the TSH receptor level because it inhibited TSH induced c-AMP accumulation and showed positive thyrotropin binding inhibitor immunoglobulin (TBI I) activity, but did not inhibit the forskolin- and (Bu)2cAMP-induced 125I uptake. Inhibition of another IgG was suggested at the post-receptor level because it did not inhibit TSH induced cAMP accumulation and showed negative TBI I activity, but inhibited forskolin- and (Bu)2cAMP-induced 125I uptake.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship among thyrotropin (TSH), thyroid stimulating immunoglobulins, and results of triiodothyronine (T3) suppression test in patients with Graves' disease

To investigate the relationship between TSH and abnormal thyroid stimulator(s) in patients with hyperthyroid Graves' disease in whom normal thyroid hormone levels in the serum were maintained by antithyroid drug therapy and in patients with euthyroid Graves' disease, determinations were made of the TSH concentration, action of thyroid stimulating immunoglobulins (TSAb and TBII), and T3 suppression. Out of thirty-three patients with hyperthyroid Graves' disease, twelve patients with subnormal TSH levels were all non-suppressible according to the T3 suppression test results and the detectability of TSAb and/or TBII was as high as 75%. In three out of five patients with euthyroid Graves' disease, the serum TSH level was subnormal. All three showed non-suppressibility in the T3 suppression test and positive action of either TSAb or TBII. One of them became clinically thyrotoxic when the TSAb activity was further increased and TBII became positive, and was therefore diagnosed as having hyperthyroid Graves' disease. The present findings suggest that there are still abnormal thyroid stimulator(s) in patients with hyperthyroid Graves' disease who have low TSH, even if their thyroid hormone concentrations remain normal. Moreover, it is likely that some of the patients with euthyroid Graves' disease are actually in a state of subclinical hyperthyroidism because of the presence of abnormal thyroid stimulator(s).

[Clinical studies on abnormal thyroid stimulators in patients with Graves' disease. I. A sensitive assay for thyroid-stimulating antibodies using cultured porcine thyroid cells and polyethylene glycol precipitation of serum]

The activities of thyroid-stimulating antibody (TSAb) in serum from patients with Graves' disease were measured by a sensitive assay, using cultured porcine thyroid cells and the precipitation from serum with polyethylene glycol (PEG), and the activities were compared with those of thyrotropin binding inhibitor immunoglobulin (TBII), measured by the commercial assay kit. Porcine thyroid cells after digestion were cultured for 15-18 hours with TSH of 1-10,000 microU/ml or the precipitations of sera from normal subjects and patients with Graves' disease or Hashimoto's thyroiditis, and then the cAMP levels in the culture medium were determined by the commercial RIA assay kit (Yamasa). The precipitation was obtained by adding 0.5 ml of 30% PEG solution to 0.5 ml serum, and was resuspended with 0.6 ml of Hanks' medium without NaCl, containing 1.5% bovine serum albumin, 20mM Hepes and 0.5 mM 3-isobutyl-1-methylxanthine. The precipitation contained about 85% of immunoglobulin and 63% of albumin of the original amount of the serum, as well as substantial TSH, when the original serum contained TSH more than 40 microU/ml. When the PEG precipitations from 10 normal subjects were incubated with the thyroid cells of 4 X 10(5) cells, the cAMP releases into the medium ranged from 83 to 124%, when the mean value was calculated as 100%. Therefore, the cAMP release of more than 130% of the amount released into the culture medium incubated with normal IgG was judged as positive TSAb activity. The minimum detectable quantities were regarded as about 5 microU/ml TSH equivalent. TSAb and TBII activities were detected in 48 (92%) and 50 (96%) of 52 patients with untreated hyperthyroid Graves' disease, respectively, and either TSAb or TBII activities were detected in 16 (80%) of 20 patients with Graves' disease maintained in a clinically euthyroid state by treatment with antithyroid drugs. TBII was positive in 10(50%) of these patients. Some patients showed distinct discrepancies in these two activities, although there was a significant positive correlation between TSAb and TBII activities (r = 0.53, p less than 0.01) in patients with untreated Graves' disease. In these patients, TSAb activities showed a significant positive correlation with values for 99mTc thyroid uptake, determined 30 min after the injection. However, they did not show any significant correlation with serum T4 or T3 concentrations. Similarly, TBII showed significant correlations with goiter size and 99mTc thyroid uptake. To conclude, the present assay for TSAb is sensitive and reproducible.(ABSTRACT TRUNCATED AT 400 WORDS)

[Clinical studies on abnormal thyroid stimulators in patients with Graves' disease. II. Clinical significance of measuring TSAb and TBII in patients with euthyroid Graves' disease and patients with hyperthyroid Graves' disease during antithyroid drug treatment]

To evaluate the clinical significance of TBII and TSAb activities in euthyroid and hyperthyroid Graves' disease, these two activities were measured in 8 patients with euthyroid Graves' disease and 29 patients with hyperthyroid Graves' disease during treatment with antithyroid drugs. In 8 patients with euthyroid Graves' disease, TBII activity was detectable only in one patient and TSAb activity detected in 3 patients, these detectabilities being much lower than those in hyperthyroid Graves' disease. However, 2 of 4 patients who had either TSAb or TBII came to have both activities, and one of them became overt hyperthyroid. In patients with hyperthyroid Graves' disease, detectabilities of these activities became lower as they became euthyroid with antithyroid drug treatment, but TSAb tended to be higher than TBII when they remained euthyroid for more than 4 months. Although the majority of the patients who had TSAb and/or TBII activities were T3 non-suppressible, patients with no TSAb and TBII activities did not necessarily show remission of the disease. The present results suggest that patients with euthyroid Graves' disease with both TBII and TSAb may be apt to become hyperthyroid, and that TSAb and TBII activities and T3 suppressibility may not be a definite criteria for the remission of Graves' disease.