ACTIONS OF CHRONIC ANABOLIC STEROID TREATMENT AND PHYSICAL EXERCISE ON PAPILLARY MUSCLE PERFORMANCE

Exhaustive and acute unusual physical exercise leads to muscle damage. Curcumin has been widely studied due to the variety of its biological activities, attributed to its antioxidant and anti-inflammatory properties. Furthermore, it has shown positive effects on physical exercise practitioners. However, there is no literature consensus on the beneficial effects of curcumin in acute physical activities performed by sedentary individuals. Therefore, we systematically reviewed evidence from clinical trials on the main effects of curcumin supplementation on inflammatory markers, sports performance, and muscle damage during acute physical exercises in these individuals. We searched PubMed/MEDLINE, Scopus, Web of Science, and Embase databases, and only original studies were analyzed according to the PRISMA guidelines. The included studies were limited to supplementation of curcumin during acute exercise. A total of 5 studies were selected. Methodological quality assessments were examined using the SYRCLE’s risk-of-bias tool. Most studies have shown positive effects of curcumin supplementation in sedentary individuals undergoing acute physical exercise. Overall, participants supplemented with curcumin showed less muscle damage, reduced inflammation, and better muscle performance. The studies showed heterogeneous data and exhibited methodological limitations; therefore, further research is necessary to ensure curcumin supplementation benefits during acute and high-intensity physical exercises. Additionally, mechanistic and highly controlled studies are required to improve the quality of the evidence and to elucidate other possible mechanisms. This study is registered with Prospero number CRD42021262718.

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Myocardial relaxation. I. Effect of nitroprusside on the tension prolongation phenomenon

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1979.237.2.h185 ◽

1979 ◽

Vol 237 (2) ◽

pp. H185-H190

Author(s):

W. H. Gaasch ◽

O. H. Bing

Keyword(s):

Papillary Muscle ◽

Left Ventricular ◽

Muscle Performance ◽

Ischemia And Reperfusion ◽

Myocardial Relaxation ◽

Dog Heart ◽

Diastolic Compliance ◽

Rat Papillary Muscle ◽

Isolated Rat ◽

Intact Heart

The effects of nitroprusside and cyanide on myocardial relaxation were studied during hypoxia and reoxygenation of isolated rat papillary muscle, and during segmental ischemia and reperfusion in the intact dog heart. Nitroprusside did not affect isolated muscle performance before or during hypoxia. During reoxygenation of hypoxic muscles, the tension prolongation phenomenon (which characterizes abnormal or prolonged relaxation) was only slightly attenuated by the addition of nitroprusside to the muscle bath; in contrast, cyanide (at concentrations that did not prevent the return of tension) abolished tension prolongation during reoxygenation. During reperfusion of ischemic segments in intact hearts, the prolongation of segment tension was not affected by systemic administration of nitroprusside, but was abolished by intracoronary cyanide. Attenuation of the tension prolongation phenomenon by nitroprusside in the isolated muscle may be due to the liberation of cyanide. Inasmuch as nitroprusside did not affect the tension prolongation phenomenon in the intact heart, it is unlikely that the influence of this drug on left ventricular diastolic compliance is mediated through an alteration in the tension prolongation phenomenon.

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Changes in LV papillary muscle performance and myosin composition with aortic insufficiency in rats

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1987.253.5.h1005 ◽

1987 ◽

Vol 253 (5) ◽

pp. H1005-H1011 ◽

Cited By ~ 1

Author(s):

C. S. Apstein ◽

Y. Lecarpentier ◽

J. J. Mercadier ◽

J. L. Martin ◽

F. Pontet ◽

...

Keyword(s):

Papillary Muscle ◽

Aortic Insufficiency ◽

Left Ventricular ◽

Muscle Performance ◽

Common Mechanism ◽

Velocity Of Shortening ◽

Isoenzyme Composition ◽

Myosin Isozyme ◽

Induced Changes ◽

Myocardial Adaptation

Aortic insufficiency was induced in rats. Left ventricular papillary muscle function was studied after 5, 12, and 40 wk and compared with the papillary muscles from sham-operated animals. The maximum unloaded velocity of shortening, Vmax, was decreased in the rats with aortic insufficiency relative to controls by 15, 20, and 34% at 5, 12, and 40 wk, respectively. The decrease in Vmax occurred concomitantly with a change in the myosin isoenzyme composition such that the V1 isoform content decreased and the V3 isoform increased. Relative to age-matched controls, the V3 content in the hearts with aortic insufficiency had increased by 80, 180, and 125% at 5, 12, and 40 wk, respectively. The decrease in Vmax in the aortic insufficiency group muscles correlated with the change in myosin isozyme composition and could not be explained by changes in collagen content. Thus aortic insufficiency induced changes in myosin isozyme content and Vmax similar to those previously observed with aortic stenosis, thus suggesting a common mechanism of myocardial adaptation to different types of mechanical overload.

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