Protective role of sex hormones in apoptosis of skeletal muscle

Abstract Angiotensin converting enzyme-2 (ACE2) is a multifunctional transmembrane protein recently recognised as the entry receptor of the virus causing COVID-19. In the renin–angiotensin system (RAS), ACE2 cleaves angiotensin II (Ang II) into angiotensin 1-7 (Ang 1-7), which is considered to exert cellular responses to counteract the activation of the RAS primarily through a receptor, Mas, in multiple organs including skeletal muscle. Previous studies have provided abundant evidence suggesting that Ang 1-7 modulates multiple signalling pathways leading to protection from pathological muscle remodelling and muscle insulin resistance. In contrast, there is relatively little evidence to support the protective role of ACE2 in skeletal muscle. The potential contribution of endogenous ACE2 to the regulation of Ang 1-7-mediated protection of these muscle pathologies is discussed in this review. Recent studies have suggested that ACE2 protects against ageing-associated muscle wasting (sarcopenia) through its function to modulate molecules outside of the RAS. Thus, the potential association of sarcopenia with ACE2 and the associated molecules outside of RAS is also presented herein. Further, we introduce the transcriptional regulation of muscle ACE2 by drugs or exercise, and briefly discuss the potential role of ACE2 in the development of COVID-19.

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The influence of sex on the olfactory function in healthy subjects

Zbornik Matice srpske za prirodne nauke ◽

10.2298/zmspn0201083s ◽

2002 ◽

pp. 83-89

Author(s):

Slobodan Savovic ◽

Vladimir Pilija ◽

Slobodanka Lemajic ◽

Maja Buljcik ◽

Dejan Nincic ◽

...

Keyword(s):

Sex Hormones ◽

Ethyl Alcohol ◽

Mental State ◽

Healthy Subjects ◽

Age Groups ◽

Protective Role ◽

Olfactory Function ◽

Age Group ◽

Phenyl Ethyl Alcohol

The sense of smell is the least examined of all senses. The significance of the organs of smell is in their influence on the mental state as well as on the vegetative, visceral and sexual functions. The objective of this experiment was to define the influence of sex on the olfactory function. It was performed on 120 subjects (60 females and 60 males) divided into three age groups (20 - 30; 31 - 40; 41 - 50 years of age). The experiment was carried out by the Fortunato-Niccolini olfactometric method using six odorous experimental substances: A - anethol, PH - phenyl-ethyl-alcohol, C citral, M - menthol, V- vanillin and P - pyridine, the thresholds of perception (TP) and identification (TI) being defined for each odorous substance. The examined females had slightly lower thresholds of perception (TP) and identification (TI) in relation to the males of the same age group. However, the differences were not statistically significant except for the group of subjects between 41 and 50 years of age where the females, being in the pre-menopause, had significantly better olfactory functions. The results can be explained by the weakening of the olfactory power as a result of ageing in both sexes, however, the females still experienced the protective role of sex hormones.

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Protective Role of Polysaccharides from Gynostemma pentaphyllum Makino Supplementation against Exhaustive Swimming Exercise-Induced Oxidative Stress in Liver and Skeletal Muscle of Mice

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.962-965.1231 ◽

2014 ◽

Vol 962-965 ◽

pp. 1231-1234

Author(s):

Hui Huang ◽

Bo Qi

Keyword(s):

Oxidative Stress ◽

Skeletal Muscle ◽

Protective Role ◽

Swimming Exercise ◽

Control Group ◽

High Dose ◽

Gynostemma Pentaphyllum ◽

Exercise Induced ◽

Different Doses

The objective of this study was to investigate the protective role of polysaccharide fromGynostemma pentaphyllumMakino (PGP) supplementation against exhaustive swimming exercise-induced oxidative stress. A total of 48 mice were randomly divided into four groups: control, low-dose, medium-dose, and high-dose PGP supplementation groups. The control group received distilled water and the supplementation groups received different doses of PGP (50, 100 and 200 mg/kg body weight) by gavage once a day for 28 consecutive days. After 28 days, the mice performed an exhaustive swimming exercise, and some biochemical parameters related to oxidative stress, including superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and malondialdehyde (MDA), were measured. The results showed that PGP supplementation could increase SOD, GPx and CAT contents, as well as decrease MDA contents in the liver and skeletal muscle of mice, which suggests that PGP supplementation has a protective role against exhaustive swimming exercise-induced oxidative stress.

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