Low protein

About: Low protein is a research topic. Over the lifetime, 8139 publications have been published within this topic receiving 213225 citations.

Influence of Protein Restriction on Immune Functions in NZB Mice

Abstract: The influence of a low protein (6%) diet on the immunologic function of NZB mice was investigated. The low protein intake was associated with decreased weight gain in both male and female NZB mice. The mice fed the low protein diet did not develop splenomegaly, which generally occurs by 7 to 10 months of age in NZB mice fed a normal amount of protein. Further, 7- to 10-month-old NZB mice fed the low protein(6%) diet, maintained: 1) more vigorous antibody production to sheep red blood cells; 2) greater capacity to produce graft-vs-host reactions, and 3) more vigorous cell-mediated "killer" cell immunity after immunization against DBA/2 mastocytoma cells than did NZB mice on a normal (22%) protein diet. The decrease of PHA and Con A response which normally occurs with aging in NZB mice was abrogated to some degree by protein restriction. However, response to LPS, which also declines with age in NZB mice, did not appear to be influenced by diet.

The Effect of Protein and Glycemic Index on Children's Body Composition: The DiOGenes Randomized Study

Abstract: OBJECTIVE: To investigate the effect of protein and glycemic index (GI) on body composition among European children in the randomized, 6-month dietary intervention DiOGenes (diet, obesity, and genes) family-based study. PATIENTS AND METHODS: In the study, 827 children (381 boys and 446 girls), aged 5 to 18 years, completed baseline examinations. Families with parents who lost ≥8% of their weight during an 8-week run-in low-calorie diet period were randomly assigned to 1 of 5 ad libitum diets: low protein (LP)/low glycemic index (LGI); LP/high GI (HGI); high protein (HP)/LGI; HP/HGI; and control diet. The target difference was 15 GI U between the LGI/HGI groups and 13 protein percentage points between the LP/HP groups. There were 658 children examined after 4 weeks. Advice on food-choice modification was provided at 6 visits during this period. No advice on weight loss was provided because the focus of the study was the ability of the diets to affect outcomes through appetite regulation. Anthropometric measurements and body composition were assessed at baseline, week 4, and week 26. RESULTS: In the study, 465 children (58.1%) completed all assessments. The achieved differences between the GI and protein groups were 2.3 GI U and 4.9 protein percentage points, respectively. The LP/HGI group increased body fat percentage significantly more than the other groups (P = .040; partial η2 = 0.039), and the percentage of overweight/obese children in the HP/LGI group decreased significantly during the intervention (P = .031). CONCLUSIONS: Neither GI nor protein had an isolated effect on body composition. However, the LP/HGI combination increased body fat, whereas the HP/LGI combination was protective against obesity in this sample of children.

Dietary Protein Restriction Decreases Insulin-Like Growth Factor I Independent of Insulin and Liver Growth Hormone Binding*

Abstract: To determine the role of hypoinsulinemia and liver somatogenic (GH) receptors in growth retardation and decreased serum insulin-like growth factor I (IGF-I) levels during protein restriction, we have used a rat model where the effects of a low protein intake on body weight (BW), serum IGF-I concentration, and liver GH binding could be evaluated in the presence of low or high insulin concentrations. Two days after being made diabetic with streptozotocin (60 mg/kg BW), 6-week-old female rats (nine per group) were begun on a low (5%) or normal (15%) protein diet, without or with insulin supplementation (3 U lente daily). Nondiabetic rats fed both diets were used as controls (nine per group). In the nondiabetic animals, 7 days of protein restriction reduced BW gain by 50% (P less than 0.001), serum insulin by 44% (P less than 0.025), and serum IGF-I concentrations by 28% (P less than 0.001) without significantly changing liver GH binding. By day 9, BW was decreased in the diabetic animals by 12%, serum insulin by 80%, serum IGF-I by 55%, and liver GH binding by 62%; these effects were similar in the 5% and 15% protein-fed rats (P less than 0.001 vs. the corresponding controls). In the diabetes fed the normal diet, insulin treatment restored BW gain, serum IGF-I, and liver GH binding to normal values. In contrast, in the diabetics fed a protein-restricted diet and treated with insulin, BW gain and serum IGF-I concentrations remained low, similar to those in the malnourished controls. This diet-induced growth attenuation was observed despite high circulating insulin (2-3 times normal values), appropriate glucose control (63 +/- 9 mg/dl), and near restoration of liver GH binding. We conclude that while both protein restriction and diabetes attenuate growth and reduce IGF-I concentrations, the effects of protein restriction are independent of the effects of insulin and probably act by alteration of postreceptor mechanisms.

Relationship Between Protein Characteristics and Instant Noodle Making Quality of Wheat Flour

Abstract: We investigated the relationship between the protein content and quality of wheat flours and characteristics of noodle dough and instant noodles using 14 hard and soft wheat flours with various protein contents and three commercial flours for making noodles. Protein content of wheat flours exhibited negative relationships with the optimum water absorption of noodle dough and lightness (L*) of the instant noodle dough sheet. Protein quality, as determined by SDS sedimentation volume and proportion of alcohol- and salt-soluble protein of flour, also influenced optimum water absorption and yellow-blueness (b*) of the noodle dough sheet. Wheat flours with high protein content (>13.6%) produced instant noodles with lower fat absorption, higher L*, lower b*, and firmer and more elastic texture than wheat flours with low protein content ( 76.8 and 36 mL) and low proportion of salt-so...

Breast cancer resistance protein: molecular target for anticancer drug resistance and pharmacokinetics/pharmacodynamics.

Abstract: Breast cancer resistance protein (BCRP) is a half-molecule ATP-binding cassette transporter that forms a functional homodimer and pumps out various anticancer agents, such as 7-ethyl-10-hydroxycamptothecin, topotecan, mitoxantrone and flavopiridol, from cells. Estrogens, such as estrone and 17β-estradiol, have been found to restore drug sensitivity levels in BCRP-transduced cells by increasing the cellular accumulation of such agents. Furthermore, synthetic estrogens, tamoxifen derivatives and phytoestrogens/flavonoids have now been identified that can effectively circumvent BCRP-mediated drug resistance. Transcellular transport experiments have shown that BCRP transports sulfated estrogens and various sulfated steroidal compounds, but not free estrogens. The kinase inhibitor gefitinib inhibited the transporter function of BCRP and reversed BCRP-mediated drug resistance both in vitro and in vivo. BCRP-transduced human epidermoid carcinoma A431 (A431/BCRP) and BCRP-transduced human non-small cell lung cancer PC-9 (PC-9/BCRP) cells showed gefitinib resistance. Physiological concentrations of estrogens (10–100 pM) reduced BCRP protein expression without affecting its mRNA levels. Two functional polymorphisms of the BCRP gene have been identified. The C376T (Q126Stop) polymorphism has a dramatic phenotype as active BCRP protein cannot be expressed from a C376T allele. The C421A (Q141K) polymorphism is also significant as Q141K-BCRP-transfected cells show markedly low protein expression levels and low-level drug resistance. Hence, individuals with C376T or C421A polymorphisms may express low levels of BCRP or none at all, resulting in hypersensitivity of normal cells to BCRP-substrate anticancer agents. In summary, both modulators of BCRP and functional single nucleotide polymorphisms within the BCRP gene affect the transporter function of the protein and thus can modulate drug sensitivity and substrate pharmacokinetics and pharmacodynamics in affected cells and individuals. (Cancer Sci 2005; 96: 457–465)