scholarly journals Testosterone, Age, and Sex Affect Platelet Responsiveness in Vitro

2021 ◽  
Vol 233 (5) ◽  
pp. e208-e209
Author(s):  
Jamie B. Hadley ◽  
Marguerite R. Kelher ◽  
Julia R. Coleman ◽  
Margot DeBot ◽  
Andrew P. Eitel ◽  
...  
Keyword(s):  
1986 ◽  
Vol 110 (3) ◽  
pp. 511-515 ◽  
Author(s):  
J. Segal ◽  
B. R. Troen

ABSTRACT The effect of age on the responsiveness of rat thymocytes to 3,5,3′-tri-iodothyronine (T3) was studied. It has been demonstrated previously that the plasma membrane-mediated effect of T3 to increase sugar uptake by rat thymocytes is influenced by age and sex. In both sexes, T3 given in vitro stimulated sugar uptake in cells from animals of 15 days of age, had no effect at 21 days and was again effective at 26 days. In the male, thymocytes from animals of 40 days of age and older were refractory to T3. However, in the female, T3, although less effective than in cells from 26-day-old animals, remained stimulatory in cells from 40- and 60-day-old rats. T3 had no effect in cells from animals of 90 days of age and older. In in-vivo studies in which female rats of 26, 60 and 90 days of age were first injected with T3 and 1 h later with [3H]2-deoxyglucose, the responsiveness of thymocytes to T3 also declined progressively with advancing age; T3 was most effective in cells from 26-day-old animals, less stimulatory in 60-day-old and essentially without effect in cells from 90-day-old animals. From these observations we have concluded that in both male and female rats the responsiveness of thymocytes to T3 declines progressively with age, and that this decline occurs at an earlier age in cells obtained from males. J. Endocr. (1986) 110, 511–515


1982 ◽  
Vol 93 (2) ◽  
pp. 177-181 ◽  
Author(s):  
Joseph Segal ◽  
B. R. Troen ◽  
S. H. Ingbar

Studies of the influence of age and sex on the concentrations of total thyroxine (T4) and 3,5,3′-tri-iodothyronine (T3) in serum and on the free T4 and free T3 indices, were conducted in Sprague–Dawley rats of the CD strain varying in age between 10 days and 12 months. Both sex- and age-related differences were found. In all age-groups studied, serum T4 concentrations were higher in the male than in the female, whereas serum T3 concentrations were higher in the female. In both sexes, concentrations of T4 and T3 in serum reached a peak early in life, between the first and second month of age, and declined thereafter. In addition, in both sexes the intensity of thyroid hormone binding, as judged from values of the in-vitro uptake of T3, did not change with age, suggesting that free T4 and T3 concentrations in the serum display the same sex differences and age-related changes as do the concentrations of total T4 and T3. It remains to be determined whether these sex-and age-related alterations in serum thyroid hormone concentration are expressed in differences in the activity of various thyroid hormone-dependent processes.


Endocrinology ◽  
2017 ◽  
Vol 159 (1) ◽  
pp. 368-387 ◽  
Author(s):  
Pilar Argente-Arizón ◽  
Francisca Díaz ◽  
Purificación Ros ◽  
Vicente Barrios ◽  
Manuel Tena-Sempere ◽  
...  

Abstract Astrocytes participate in both physiological and pathophysiological responses to metabolic and nutrient signals. Although most studies have focused on the astrocytic response to weight gain due to high-fat/high-carbohydrate intake, surplus intake of a balanced diet also induces excess weight gain. We have accessed the effects of neonatal overnutrition, which has both age- and sex-dependent effects on weight gain, on hypothalamic inflammation/gliosis. Although both male and female Wistar rats accumulate excessive fat mass as early as postnatal day (PND) 10 with neonatal overnutrition, no increase in hypothalamic cytokine levels, markers of astrocytes or microglia, or inflammatory signaling pathways were observed. At PND 50, no effect of neonatal overnutriton was found in either sex, whereas at PND 150, males again weighed significantly more than their controls, and this was coincident with an increase in markers of inflammation and astrogliosis in the hypothalamus. Circulating triglycerides and free fatty acids were also elevated in these males, but not in females or in either sex at PND 10. Thus, the effects of fatty acids and estrogens on astrocytes in vitro were analyzed. Our results indicate that changes in circulating fatty acid levels may be involved in the induction of hypothalamic inflammation/gliosis in excess weight gain, even on a normal diet, and that estrogens could participate in the protection of females from these processes. In conclusion, the interaction of developmental influences, dietary composition, age, and sex determines the central inflammatory response and the associated long-term outcomes of excess weight gain.


Endocrinology ◽  
1987 ◽  
Vol 120 (4) ◽  
pp. 1422-1429 ◽  
Author(s):  
MARIE-THÉRÈSE CORVOL ◽  
ANTONIO CARRASCOSA ◽  
LYDIA TSAGRIS ◽  
ODILE BLANCHARD ◽  
RAPHAËL RAPPAPORT

2021 ◽  
Vol 154 (9) ◽  
Author(s):  
Mina P. Peyton ◽  
Dawn A. Lowe

Twitch force potentiation of fast-twitch skeletal muscle is produced by repetitive stimulation that can be achieved from either (1) the staircase effect (continual low frequency stimulation) or (2) post-tetanic potentiation (a 1–2 s high-frequency tetanic stimulation). Previous studies examining twitch force potentiation have been conducted in vitro and shown that it is related to phosphorylation of myosin regulatory light chain (pRLC). We previously found, in vitro, reduced potentiation of twitch force and decreased pRLC in ovariectomized (Ovx, estrogen-deficient) compared with sham-operated (estrogen-replete) mice. Thus, we questioned whether this phenomenon occurred in vivo and whether age and sex would affect the potentiation of twitch force. Using an in vivo post-tetanic potentiation method (one twitch contraction followed by a tetanic contraction—100 Hz for 1,000 ms with 0.01 ms pulses, and two post-tetanic twitch contractions), we investigated twitch torque potentiation in C57BL/6 young and old, male and female mice. There were significant main effects of sex (P < 0.001) and age (P < 0.001) on body mass and significant main effects of sex (P < 0.001) on tibialis anterior and extensor digitorum longus muscle masses, with males and aged being relatively greater. Analysis of twitch torque using a three-way ANOVA across time, age, and sex showed a significant main effect of time (pre < post; P < 0.001), time × age (P = 0.038), and time × sex (P = 0.028), indicating potentiation occurred in young and old, males and females. Analysis of twitch torque potentiation (percent increase) using a two-way ANOVA revealed a significant main effect of age (young = 45.16 ± 2.04 versus old = 27.88 ± 9.96; P < 0.001) with no effect of sex (P = 0.215). In summary, enhanced generation of twitch force of skeletal muscle using a post-tetanic potentiation method does occur in vivo and is affected by age but not sex, as there is greater twitch torque potentiation in young than old mice.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
L.M Rincon ◽  
E.M Rodriguez-Serrano ◽  
P Gonzalez-Portilla ◽  
E Conde ◽  
M Sanmartin ◽  
...  

Abstract Introduction and aim Adverse ventricular remodelling and heart failure (HF) are frequent complications of acute myocardial infarction (MI), but no reliable methods are currently available for prediction. MicroRNAs (miRNAs) can be used as biomarkers and they play a crucial role in multiple diseases onset and evolution. The aim of our study was to identify and validate a panel of serum miRNAs with differential expression in MI and test their prognostic ability to predict chronic HF. Methods Sequential approach with several models: 1) Initial selection of miRNAs by a 762 miRNA hybridization array with samples from 12 patients with acute MI and 10 age and sex-matched controls; 2) Validation of selected miRNAs in a prospective study with consecutive enrolment of patients with type 1 MI at the Cardiac ICU of a tertiary hospital; two independent cohorts were included (2013–2014 and 2017–2019) with clinical and CV imaging assessment at baseline and long-term follow-up; serum miRNAs and other biomarkers (BNP, NT-proBNP, troponin, etc) were studied; the composite HF-related outcome included HF hospitalizations and CV mortality; 30 age and sex-adjusted controls were studied for miRNAs comparison; miRNA signature study was completed with 3) in vitro model of hypoxia ±nutrient supply deprivation in H9C2 cardiomyocytes, 4) in vivo rat model of ischemia-reperfusion and 5) permanent coronary occlusion. All procedures were approved by the Ethics Committee (refs. 175/13 & 061/16), the Animals Ethics Committee (ref. 298/16) and complied with the Declaration of Helsinki. All patients provided written informed consent. Results 14 miRNAs were initially identified with highest differentiation between MI and controls. In the validation study, 311 patients with MI were enrolled, mean age 60±15, 81% male; ST elevation MI 65%, GRACE risk score 144±45, Killip class ≥II 23%, LVEF<50% at discharge 46% and NT-proBNP 3091±5997 pg/ml. miR-210, miR-21, miR-23 and miR-221 discriminated between patients with more severe form of MI presentation by Killip class (figure 1-B); in addition, GRACE risk score statistically correlated with miR-21, miR-221, miR-27, miR-93, miR-23, miR-148, miR-107, miR-210 and miR-144. Among markers of acute HF, miR-21, miR-23, miR-27, miR-210 and miR-221 significantly correlated with NT-proBNP (figure 1-C) and BNP levels. In parallel, miR-210, miR-21, miR-23, miR-106, miR-221, miR-27 and miR-93 correlated with left ventricular ejection fraction (LVEF). Finally, miR-21, miR-23, miR-210 and miR-221 associated with patients' long-term survival free of long-term HF-related events. Both in vitro and in vivo experimental models served as confirmation of the importance of these outlined miRNAs in cardiomyocyte response to ischemic stress and ventricular remodelling. Conclusions We identified a signature of microRNAs associated with adverse ventricular remodelling and poor long-term outcome after MI, that could serve as biomarkers involved in HF progression. Figure 1 Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III


Sign in / Sign up

Export Citation Format

Share Document