-
1.
Dietary flavanols restore hippocampal-dependent memory in older adults with lower diet quality and lower habitual flavanol consumption.
Brickman, AM, Yeung, LK, Alschuler, DM, Ottaviani, JI, Kuhnle, GGC, Sloan, RP, Luttmann-Gibson, H, Copeland, T, Schroeter, H, Sesso, HD, et al
Proceedings of the National Academy of Sciences of the United States of America. 2023;120(23):e2216932120
-
-
-
Free full text
Plain language summary
“Cognitive aging” is a term used to describe how some of our cognitive abilities decline during the aging process, independent of late-life cognitive diseases. Because cognitive aging is meaningfully disruptive to our lives, it is biomedically justified to identify its etiologic factors. The current study was ancillary to COSMOS and termed COSMOS-Web. COSMOS was designed to examine the effects of cocoa extract and multivitamin supplementation on total cardiovascular disease and total invasive cancer. For this study, the focus is on the cocoa extract intervention only. Participants were randomly assigned to a 3-year intervention of cocoa extract or a placebo. Results showed that a flavanol intervention-based restoration of memory was observed in the lower tertile of habitual diet quality and in the subset of participants with lower habitual flavanol consumption. The improvement in memory was apparent after 12 months of intervention and appeared to be sustained over the 3 years of follow-up. Additionally, diet quality is a key lifestyle factor linked to the hippocampal and not to the prefrontal component of cognitive aging. Authors concluded that habitual flavanol consumption and diet quality at baseline are positively and selectively correlated with hippocampal-dependent memory. Improvements in the flavanol biomarker over the trial were associated with improving memory.
Abstract
Dietary flavanols are food constituents found in certain fruits and vegetables that have been linked to cognitive aging. Previous studies suggested that consumption of dietary flavanols might specifically be associated with the hippocampal-dependent memory component of cognitive aging and that memory benefits of a flavanol intervention might depend on habitual diet quality. Here, we tested these hypotheses in the context of a large-scale study of 3,562 older adults, who were randomly assigned to a 3-y intervention of cocoa extract (500 mg of cocoa flavanols per day) or a placebo [(COcoa Supplement and Multivitamin Outcomes Study) COSMOS-Web, NCT04582617]. Using the alternative Healthy Eating Index in all participants and a urine-based biomarker of flavanol intake in a subset of participants [n = 1,361], we show that habitual flavanol consumption and diet quality at baseline are positively and selectively correlated with hippocampal-dependent memory. While the prespecified primary end point testing for an intervention-related improvement in memory in all participants after 1 y was not statistically significant, the flavanol intervention restored memory among participants in lower tertiles of habitual diet quality or habitual flavanol consumption. Increases in the flavanol biomarker over the course of the trial were associated with improving memory. Collectively, our results allow dietary flavanols to be considered in the context of a depletion-repletion paradigm and suggest that low flavanol consumption can act as a driver of the hippocampal-dependent component of cognitive aging.
-
2.
Interaction Between Type 2 Diabetes Prevention Strategies and Genetic Determinants of Coronary Artery Disease on Cardiometabolic Risk Factors.
Merino, J, Jablonski, KA, Mercader, JM, Kahn, SE, Chen, L, Harden, M, Delahanty, LM, Araneta, MRG, Walford, GA, Jacobs, SBR, et al
Diabetes. 2020;69(1):112-120
-
-
-
Free full text
-
Plain language summary
Individual risk of Coronary Artery Disease (CAD) and type 2 diabetes reflects the interplay between lifestyle behaviours acting on a backdrop of genetic predisposition. The aim of this study was to examine whether type 2 diabetes prevention strategies, either an intensive lifestyle intervention (ILS) or metformin treatment (MET), modify the association between CAD genetic risk and cardiometabolic risk factors (CRFs) in participants at high risk of type 2 diabetes. The study is a randomised controlled trial were participants were randomly allocated to one of the three groups; ILS (n = 1,079), MET (850 mg twice daily [n = 1,073]), or placebo (n = 1,082). Results indicate that there weren’t major significant differences in baseline characteristics, except for lower high-density lipoprotein and higher triglyceride in the placebo individuals compared with individuals assigned to MET or ILS. In fact, either an ILS or MET has a beneficial effect on 1-year change in different CRFs. Authors conclude that type 2 diabetes–preventive strategies for individuals at high risk of type 2 diabetes provide beneficial effects on CRFs regardless of CAD genetic risk profile.
Abstract
Coronary artery disease (CAD) is more frequent among individuals with dysglycemia. Preventive interventions for diabetes can improve cardiometabolic risk factors (CRFs), but it is unclear whether the benefits on CRFs are similar for individuals at different genetic risk for CAD. We built a 201-variant polygenic risk score (PRS) for CAD and tested for interaction with diabetes prevention strategies on 1-year changes in CRFs in 2,658 Diabetes Prevention Program (DPP) participants. We also examined whether separate lifestyle behaviors interact with PRS and affect changes in CRFs in each intervention group. Participants in both the lifestyle and metformin interventions had greater improvement in the majority of recognized CRFs compared with placebo (P < 0.001) irrespective of CAD genetic risk (P interaction > 0.05). We detected nominal significant interactions between PRS and dietary quality and physical activity on 1-year change in BMI, fasting glucose, triglycerides, and HDL cholesterol in individuals randomized to metformin or placebo, but none of them achieved the multiple-testing correction for significance. This study confirms that diabetes preventive interventions improve CRFs regardless of CAD genetic risk and delivers hypothesis-generating data on the varying benefit of increasing physical activity and improving diet on intermediate cardiovascular risk factors depending on individual CAD genetic risk profile.
-
3.
Changes in Visceral Adiposity, Subcutaneous Adiposity, and Sex Hormones in the Diabetes Prevention Program.
Kim, C, Dabelea, D, Kalyani, RR, Christophi, CA, Bray, GA, Pi-Sunyer, X, Darwin, CH, Yalamanchi, S, Barrett-Connor, E, Golden, SH, et al
The Journal of clinical endocrinology and metabolism. 2017;102(9):3381-3389
-
-
-
Free full text
-
Plain language summary
It is not currently known to what extent changes in different types of fat stores (visceral fat that surrounds organs and subcutaneous fat that sits under the surface of the skin) relate to changes in sex hormones. This study was a secondary analysis of a randomised controlled trial including 555 individuals. It examined whether changes to visceral and subcutaneous fat were associated with changes in sex hormones (DHEA, testosterone, oestrogen and sex hormone binding globulin - SHBG) among overweight individuals with glucose intolerance under the care of a diabetes program. Participants were randomly assigned to an intensive lifestyle modification programme (goals for weight reduction and 150 mins exercise weekly), medication (metformin) or placebo for 12 months. The authors found that among men, reductions in both types of fat were associated with significant increases in total testosterone and SHBG. Among women, reductions in both types of fat were associated with increases in SHBG and associations with estrone differed by menopausal status. No associations were found between changes in fat stores and estradiol or DHEA. The authors conclude that weight loss may affect sex hormone profiles via reductions in visceral and subcutaneous fat. -
Abstract
Context: The degree to which changes in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) relate to corresponding changes in plasma sex steroids is not known. Objective: We examined whether changes in VAT and SAT areas assessed by computed tomography were associated with changes in sex hormones [dehydroepiandrosterone sulfate (DHEAS), testosterone, estradiol, estrone, and sex hormone binding globulin (SHBG)] among Diabetes Prevention Program participants. Design: Secondary analysis of a randomized trial. Participants: Overweight and glucose-intolerant men (n = 246) and women (n = 309). Interventions: Intensive lifestyle change with goals of weight reduction and 150 min/wk of moderate intensity exercise or metformin administered 850 mg twice a day or placebo. Main Outcome Measures: Associations between changes in VAT, SAT, and sex hormone changes over 1 year. Results: Among men, reductions in VAT and SAT were both independently associated with significant increases in total testosterone and SHBG in fully adjusted models. Among women, reductions in VAT and SAT were both independently associated with increases in SHBG and associations with estrone differed by menopausal status. Associations were similar by race/ethnicity and by randomization arm. No significant associations were observed between change in fat depot with change in estradiol or DHEAS. Conclusions: Among overweight adults with impaired glucose intolerance, reductions in either VAT and SAT were associated with increased total testosterone in men and higher SHBG in men and women. Weight loss may affect sex hormone profiles via reductions in visceral and subcutaneous fat.
-
4.
Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes.
Wing, RR, Bolin, P, Brancati, FL, Bray, GA, Clark, JM, Coday, M, Crow, RS, Curtis, JM, Egan, CM, Espeland, MA, et al
The New England journal of medicine. 2013;369(2):145-54
-
-
-
Free full text
-
Plain language summary
Weight loss is recommended for overweight or obese patients with type 2 diabetes as it increases glycaemic control, reduces risk factors of cardiovascular disease and improves overall quality of life. These benefits, however, are based on short-term studies and the long-term effects of weight loss in this population have not been examined. The aim of this randomised trial was to elucidate whether an intensive lifestyle intervention of weight loss and increased physical activity would decrease cardiovascular morbidity and mortality in overweight or obese adults with type 2 diabetes. Participants were either assigned to an intervention group receiving diet and exercise counselling, or a control group receiving diabetes support and education. A total of 5145 patients were enrolled in the study and the median follow-up was nearly 10 years. The findings of this study showed that an intensive lifestyle intervention did not reduce the risk of cardiovascular morbidity and mortality, as compared with a control programme of diabetes support and education, among overweight and obese patients. While this primary outcome was not reduced, participants in the intervention group experienced various clinically beneficial outcomes throughout the follow-up period.
Abstract
BACKGROUND Weight loss is recommended for overweight or obese patients with type 2 diabetes on the basis of short-term studies, but long-term effects on cardiovascular disease remain unknown. We examined whether an intensive lifestyle intervention for weight loss would decrease cardiovascular morbidity and mortality among such patients. METHODS In 16 study centers in the United States, we randomly assigned 5145 overweight or obese patients with type 2 diabetes to participate in an intensive lifestyle intervention that promoted weight loss through decreased caloric intake and increased physical activity (intervention group) or to receive diabetes support and education (control group). The primary outcome was a composite of death from cardiovascular causes, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for angina during a maximum follow-up of 13.5 years. RESULTS The trial was stopped early on the basis of a futility analysis when the median follow-up was 9.6 years. Weight loss was greater in the intervention group than in the control group throughout the study (8.6% vs. 0.7% at 1 year; 6.0% vs. 3.5% at study end). The intensive lifestyle intervention also produced greater reductions in glycated hemoglobin and greater initial improvements in fitness and all cardiovascular risk factors, except for low-density-lipoprotein cholesterol levels. The primary outcome occurred in 403 patients in the intervention group and in 418 in the control group (1.83 and 1.92 events per 100 person-years, respectively; hazard ratio in the intervention group, 0.95; 95% confidence interval, 0.83 to 1.09; P=0.51). CONCLUSIONS An intensive lifestyle intervention focusing on weight loss did not reduce the rate of cardiovascular events in overweight or obese adults with type 2 diabetes. (Funded by the National Institutes of Health and others; Look AHEAD ClinicalTrials.gov number, NCT00017953.).
-
5.
A prospective study of meat and meat mutagens and prostate cancer risk.
Cross, AJ, Peters, U, Kirsh, VA, Andriole, GL, Reding, D, Hayes, RB, Sinha, R
Cancer research. 2005;65(24):11779-84
-
-
-
Plain language summary
Meat cooked at high temperatures is a source of carcinogens (heterocyclic amines and polycyclic aromatic hydrocarbons). The formation of these substances depends on the meat type, and is highest in meats cooked by high-temperature cooking methods. The aim of the study was to determine whether meat intake or meat-related mutagens was associated with increased prostate cancer risk. This was a prospective cohort study of 29,361 men aged between 55 and 74. Results show that a consumption of more than 10 g per day of very well done meat was associated with a 42% increased risk for prostate cancer and a 69% increased risk for incident disease. A high intake of the carcinogens under study was associated with a 22% increased risk for prostate cancer and a 28% increased risk for incident disease. The study concluded that there is a positive association between prostate cancer risk and a high intake of very well done meat.
Abstract
High-temperature cooked meat contains heterocyclic amines, including 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and polycyclic aromatic hydrocarbons, such as benzo(a)pyrene (BaP). In rodents, a high intake of PhIP induces prostate tumors. We prospectively investigated the association between meat and meat mutagens, specifically PhIP, and prostate cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Diet was assessed using a 137-item food frequency questionnaire and a detailed meat-cooking questionnaire linked to a database for BaP and the heterocyclic amines 2-amino-3,8-dimethylimidazo[4,5-b]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx), and PhIP. During follow-up, we ascertained a total of 1,338 prostate cancer cases among 29,361 men; of these, 868 were incident cases (diagnosed after the first year of follow-up) and 520 were advanced cases (stage III or IV or a Gleason score of > or =7). Total, red, or white meat intake was not associated with prostate cancer risk. More than 10 g/d of very well done meat, compared with no consumption, was associated with a 1.4-fold increased risk of prostate cancer [95% confidence interval (95% CI), 1.05-1.92] and a 1.7-fold increased risk (95% CI, 1.19-2.40) of incident disease. Although there was no association with MeIQx and DiMeIQx, the highest quintile of PhIP was associated with a 1.2-fold increased risk of prostate cancer (95% CI, 1.01-1.48) and a 1.3-fold increased risk of incident disease (95% CI, 1.01-1.61). In conclusion, very well done meat was positively associated with prostate cancer risk. In addition, this study lends epidemiologic support to the animal studies, which have implicated PhIP as a prostate carcinogen.
-
6.
Effects of alcohol on insulin-like growth factor I and insulin-like growth factor binding protein 3 in postmenopausal women.
Lavigne, JA, Baer, DJ, Wimbrow, HH, Albert, PS, Brown, ED, Judd, JT, Campbell, WS, Giffen, CA, Dorgan, JF, Hartman, TJ, et al
The American journal of clinical nutrition. 2005;81(2):503-7
-
-
-
Free full text
-
Plain language summary
Both alcohol and the endocrine hormone insulin-like growth factor (IGF-1) have been linked to increased breast cancer risk. However, the link with breast cancer is stronger in pre-menopausal women but most studies have not distinguished between pre and post-menopausal individuals. This randomly controlled, crossover study looked at how IGF-1 and its major binding protein IGFBP-3 were affected by alcohol in 31 pre-menopausal women, it also considered if levels were affected by the menstrual cycle. The study concluded that there is a link between alcohol and the reduction of IGF-1 but no effect on IGFBP-3 They also found that IGF-1 serum levels significantly increase during the later stages of the menstruation cycle regardless of alcohol intake. Further studies are needed to understand the balance of alcohol intake and how that alters an increase or decrease in breast cancer risk.
Abstract
BACKGROUND Increased circulating insulin-like growth factor I (IGF-I) concentrations, frequently adjusted for IGF binding protein 3 (IGFBP-3), have been associated with increased risk of several types of cancer, including colon, prostate, and breast. Studies have suggested that alcohol may affect IGF-I or IGFBP-3; however, controlled feeding studies to assess alcohol's effects on IGF-I or IGFBP-3 have not been conducted. OBJECTIVE To determine whether chronic, moderate alcohol intake affects serum IGF-I or IGFBP-3 concentrations, we performed a controlled, crossover feeding study. DESIGN Fifty-three postmenopausal women were randomly assigned to consume 0 g (control), 15 g (one drink), or 30 g (2 drinks) alcohol daily for 8 wk and were rotated through the other 2 intake levels in random order. All foods and beverages were provided during the intervention. Individuals were monitored and calories adjusted to maintain constant weight, and serum was collected at the end of each diet period. RESULTS Compared with the effects of 0 g alcohol/d, IGF-I concentrations were nearly unchanged by 15 g alcohol/d (0.8%; 95% CI: -3.2%, 3.5%) but decreased significantly by 4.9% (95% CI: -8.0%, -1.6%) with 30 g alcohol/d. IGFBP-3 concentrations significantly increased by 3.0% (95% CI: 0.4%, 5.6%) with 15 g alcohol/d but did not increase significantly with 30 g/d (1.8%; 95% CI: -0.9%, 4.5%). CONCLUSIONS To our knowledge, this is the first published controlled diet study to find that in postmenopausal women, when weight is kept constant, alcohol consumption reduces the amount of serum IGF-I potentially available for receptor binding. These findings suggest that the effect of alcohol intake should be considered in studies of IGF-I, IGFBP-3, and cancer in postmenopausal women.
-
7.
Effects of a 2-year randomized soy intervention on sex hormone levels in premenopausal women.
Maskarinec, G, Franke, AA, Williams, AE, Hebshi, S, Oshiro, C, Murphy, S, Stanczyk, FZ
Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. 2004;13(11 Pt 1):1736-44
-
-
Plain language summary
Countries that have a high consumption of soy, such as Japan and China, tend to have lower breast cancer rates. Soy contains isoflavones, phytoestrogens which may have oestrogenic and antieostrogenic effects. The aim of this trial was to examine the effect of soy foods on menstrual cycle length and circulating sex hormone levels. 189 healthy premenopausal women completed the 2-year study, during which the treatment group consumed two daily servings of soy foods (tofu, soy milk, roasted soy nuts, soy protein powder or soy protein bars) containing a total of 50 mg of isoflavones. The control group maintained their regular diet. Blood samples were taken 5 days after ovulation in months 0, 3, 6, 12 and 24. Soy did not have any significant effects on the levels of circulating sex hormones or length of menstrual cycle. The authors concluded that any preventative effects of soy on breast cancer risk may be mediated by mechanisms other than its effect on circulating sex hormone levels.
Abstract
OBJECTIVE Several epidemiologic studies have described protective effects of soy consumption against breast cancer. The goal of this trial among premenopausal women was to examine the effect of soy foods on menstrual cycle length and circulating sex hormone levels. METHODS This 2-year dietary intervention randomized 220 healthy premenopausal women. The intervention group consumed two daily servings of soy foods containing approximately 50 mg of isoflavones; the control group maintained their regular diet. Five blood samples (obtained in months 0, 3, 6, 12, and 24) were taken 5 days after ovulation as determined by an ovulation kit. The serum samples were analyzed for estrone, estradiol, sex hormone binding globulin, androstenedione, and progesterone by immunoassay. RESULTS At baseline, both groups had similar demographic, anthropometric, and nutritional characteristics. The dropout rates of 15.6% (17 of 109) in the intervention group and 12.6% (14 of 111) in the control group did not differ significantly. According to soy intake logs, 24-hour recalls, and urinary isoflavone excretion, the women closely adhered to the study regimen. Menstrual cycles became slightly shorter in both groups but did not differ by group. Mixed general linear models indicated no significant intervention effect on any of the serum hormones. However, androstenedione and progesterone decreased significantly over time in both groups. CONCLUSIONS The results of this study suggest that the preventive effects of soy on breast cancer risk in premenopausal women may not be mediated by circulating sex hormone levels. Different mechanisms of actions or effects of exposure earlier in life are alternate hypotheses that require further investigation.
-
8.
Antioxidant supplementation and nasal inflammatory responses among young asthmatics exposed to high levels of ozone.
Sienra-Monge, JJ, Ramirez-Aguilar, M, Moreno-Macias, H, Reyes-Ruiz, NI, Del Río-Navarro, BE, Ruiz-Navarro, MX, Hatch, G, Crissman, K, Slade, R, Devlin, RB, et al
Clinical and experimental immunology. 2004;138(2):317-22
-
-
-
Free full text
-
Plain language summary
Exposure to air pollution has been related to an increased occurrence and severity of asthma. In this double-blind, randomised trial, a group of asthmatic children in Mexico City were given either a daily supplement containing 250mg of vitamin C and 50mg of vitamin E, or a placebo pill, for 12 weeks. Scientists measured inflammatory markers in the nasal passages of the children after being exposed to air pollution. Children who received the vitamin supplement did not experience an increase in inflammation after being exposed to air pollution, whereas children given the placebo did. The authors concluded that supplementation with antioxidants such as vitamin C and vitamin E might decrease nasal inflammation in children with asthma who are exposed to air pollution.
Abstract
The inflammatory response to ozone in atopic asthma suggests that soluble mediators of inflammation are released in response to oxidant stress. Antioxidants may alleviate additional oxidative stress associated with photochemical oxidant pollution. This study investigates the impact of antioxidant supplementation on the nasal inflammatory response to ozone exposure in atopic asthmatic children. We conducted a randomized trial using a double-blinded design. Children with asthma (n = 117), residents of Mexico City, were given randomly a daily supplement of vitamins (50 mg/day of vitamin E and 250 mg/day of vitamin C) or placebo. Nasal lavages were performed three times during the 4-month follow-up and analysed for content of interleukin-6 (IL-6), IL-8, uric acid and glutathione (GSx). IL-6 levels in the nasal lavage were increased significantly in the placebo group after ozone exposure while no increase was observed in the supplement group. The difference in response to ozone exposure between the two groups was significant (P = 0.02). Results were similar for IL-8, but with no significant difference between the groups (P = 0.12). GSx decreased significantly in both groups. Uric acid decreased slightly in the placebo group. Our data suggest that vitamin C and E supplementation above the minimum dietary requirement in asthmatic children with a low intake of vitamin E might provide some protection against the nasal acute inflammatory response to ozone.
-
9.
Sympathetic alterations after sodium restriction and short-term captopril administration.
Mills, PJ, Dimsdale, JE, Ziegler, MG, Hauger, RL, Nelesen, RA, Brown, MR
Journal of the American College of Cardiology. 1993;21(1):177-81
-
-
-
Free full text
Plain language summary
Angiotensin-converting enzyme (ACE) inhibitors are widely used for treating hypertension. While it is known that the sympathetic nervous system is involved in the therapeutic action of ACE inhibitors, the mechanisms remain unclear. The purpose of this crossover study was to examine the effects of short-term ACE inhibitors during sodium restriction on several markers of sympathetic activity in 12 hypertensive and 20 normotensive men. The participants consumed an isocaloric, low sodium diet and either received captopril or placebo twice daily for 5 days. This study identified potential mechanisms by which captopril acts on sympathetic nervous system to cause increased cardiac output and decreased peripheral resistance. Based on this study, the authors conclude that the therapeutic effects of short-term ACE inhibitor administration involve components of the sympathetic nervous system.
Abstract
OBJECTIVES The purpose of this study was to examine the effects of short-term captopril therapy during sodium restriction on several markers of the sympathetic nervous system, including plasma norepinephrine, neuropeptide Y, beta-adrenergic receptors and cortisol. BACKGROUND Recent studies suggest that the therapeutic effects of converting enzyme inhibitors involve not only the renin-angiotensin and prostaglandin systems but also the sympathetic system. METHODS Twelve hypertensive and 20 normotensive men were studied after 2 5-day hospital stays during which they consumed a 10-mEq sodium diet and received captopril (25 mg twice daily) or placebo in a double-blind crossover study. RESULTS Captopril decreased neuropeptide Y (p < 0.05) and angiotensin II (p < 0.01) and increased isoproterenol-stimulated cyclic adenosine monophosphate (AMP) in lymphocytes (p < 0.03), plasma norepinephrine (p < 0.02), cortisol (p < 0.05) and renin (p < 0.001) in both hypertensive and normotensive subjects. Hypertensive subjects had an increased beta-adrenergic receptor density (p < 0.02) and a greater decrease in diastolic blood pressure compared with normotensive subjects (p < 0.02). CONCLUSIONS The results of this study suggest that the short-term therapeutic effects of captopril may involve concerted changes in key components of the sympathetic nervous system. These findings, such as decreased neuropeptide Y combined with increased norepinephrine and beta-adrenergic receptors, are compatible with the observation of increased cardiac output and decreased peripheral resistance after short-term angiotensin-converting enzyme inhibition.
-
10.
Sepsis alters skeletal muscle energetics and membrane function.
Jacobs, DO, Kobayashi, T, Imagire, J, Grant, C, Kesselly, B, Wilmore, DW
Surgery. 1991;110(2):318-25; 325-6
-
-
Plain language summary
Polycystic ovary syndrome (PCOS) is an endocrine disorder found in approximately 6.5% of reproductive-age women. It is often associated with obesity, insulin resistance and menstrual irregularity. Insulin inhibits the production of sex hormone binding globulin (SHBG) and stimulates ovarian P450c17 alpha activity and androgen production. This study aimed to add to the research on dietary interventions for PCOS. The intervention was three 16 day eucaloric diets, which were either enriched with mono saturated fatty acids (MUFAs) (17% energy) or low in carbohydrate (43% energy). The three intervention periods were separated by 3 week wash out periods and included 11 women. The study found that the low carbohydrate diet decreased fasting insulin, but no impact on testosterone, LH, FSH or DHEA. The researchers concluded that a modest reduction in insulin may over time, improve endocrine outcomes in those with PCOS.
Abstract
The effects of sepsis on skeletal muscle energetics and membrane function are poorly understood, and the time course of changes in energy metabolism are unclear. To clarify these relationships, high energy phosphate ratios, intracellular pH, and phosphocreatine breakdown rates were measured in vivo in the gastrocnemius muscle of adult male Wistar rats after cecal ligation and puncture or sham operation with 31P magnetic resonance spectroscopy. Adenosine triphosphate (ATP) concentration and Na(+)-K+ ATPase and creatine kinase activities were determined in vitro. Within 24 hours, Na(+)-K+ ATPase activity increased by 60% in rats with cecal ligation and puncture, all of which had positive bacterial cultures, as compared to none of the sham-operated controls. Phosphocreatine/ATP ratios decreased by 20% in association with a quantitatively similar increase in phosphocreatine breakdown (9.7 +/- 0.5 vs 11.9 +/- 0.5 mumoles/gm wet wt/sec; p = 0.01). ATP concentrations were maintained, and intracellular pH did not change significantly. In this model, changes in phosphocreatine breakdown were not related to total creatine kinase activity, which did not change significantly, or increases in adenosine 5'-diphosphate (ADP) concentration (62 +/- 8 vs 92 +/- 8 mumols/L; p = 0.02). Thus, in early sepsis before a measurable decrease in pH occurs, ATP is utilized at an increased rate to help maintain ionic balance and/or to support other metabolic processes. Phosphocreatine stores are used to buffer ATP concentrations.