Effect of long-term hyperhomocysteinemia on myocardial structure and function in hypertensive rats

Severe caloric restriction (sCR) increases the risk for acute cardiovascular disease. Less understood are the long-term effects on cardiovascular disease risk after the sCR period has ended. We investigated the effects of sCR on heart structure and function months after refeeding (sCR-Refed). Female Fischer rats (3-months-old) were maintained on (CT) ad libitum or a 60% caloric restricted diet for 2 weeks. Thereafter, all rats received ad libitum chow for 3 months and they were analyzed by precision ultrasound to assess their heart function. After imaging, the animals were sacrificed and the hearts were subjected to ischemia-reperfusion (I/R) using a Langendorff preparation. After 2 weeks of sCR, rats lost 15% of their initial body weight (BW) [% (100*(Final-Initial/Initial)): CT, 1.5±0.8 vs sCR, -15.4±1.1; p<0.001;n=8]. After 3 months of refeeding, there was no detectable difference in BW between CT and sFR-Refed groups. Isolated hearts from the sCR-Refed rats exhibited worse myocardial pathology after I/R compared to CT rats. The parallel orientation of myofibers and striations normally present in cardiomyocytes was lost in sCR-Refed rats. Further analysis revealed uneven blood-filling of the microcirculatory vessels and prominent interstitial edema of the myocardium. Hearts from sCR-Refed rats had more atrophied cardiomyocytes than CT [Atrophied/Total (%): CT, 0.2±0.1 vs sCR-Refed, 50.6±1.1; p<0.001; n=5]. The number of arrhythmic events during a 30 min ischemic interval in isolated hearts doubled after 2 weeks on the sCR diet ( data not shown ) and remained doubled 3 months later [Arrhythmias (% of time): CT, 34±8 vs sCR-Refed, 68±9; p=0.02; n=8]. Ultrasound imaging showed no difference in stroke volume, coronary perfusion pressure and left ventricular mass. However, the thickness of the left ventricular posterior wall was significantly reduced in sCR-Refed rats [(mm): CT, 2.55 ±0.03 vs sCR-Refed, 2.10±0.04; p=0.002; n=4]. These findings indicate heart structure and function remained damaged months after the sCR period ended and BW was restored. These studies have adverse cardiovascular risk implications for who are subjected either voluntarily (crash diets) or involuntarily (very low food security) to periods of inadequate caloric intake.

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Effect of empagliflozin on myocardial structure and function in patients with type 2 diabetes at high cardiovascular risk: the SIMPLE randomized clinical trial

The International Journal of Cardiovascular Imaging ◽

10.1007/s10554-021-02443-5 ◽

2021 ◽

Author(s):

Mads Ersbøll ◽

Mikkel Jürgens ◽

Philip Hasbak ◽

Andreas Kjær ◽

Emil Wolsk ◽

...

Keyword(s):

Type 2 Diabetes ◽

Clinical Trial ◽

Cardiovascular Risk ◽

Randomized Clinical Trial ◽

Structure And Function ◽

High Cardiovascular Risk ◽

Myocardial Structure ◽

And Function

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Long-term changes in structure and function of a tropical headwater stream following a disease-driven amphibian decline

Freshwater Biology ◽

10.1111/fwb.12505 ◽

2014 ◽

Vol 60 (3) ◽

pp. 575-589 ◽

Cited By ~ 13

Author(s):

Heidi M. Rantala ◽

Amanda M. Nelson ◽

Jessica N. Fulgoni ◽

Matt R. Whiles ◽

Robert O. Hall ◽

...

Keyword(s):

Amphibian Decline ◽

Structure And Function ◽

Headwater Stream ◽

Long Term Changes ◽

And Function

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Alterations of the thyroid structure and function in experimental hypopinealism

Problems of Endocrinology ◽

10.14341/probl201157232-35 ◽

2011 ◽

Vol 57 (2) ◽

pp. 32-35

Author(s):

L A Bondarenko ◽

L Iu Sergienko ◽

N N Sotnik ◽

A N Cherevko

Keyword(s):

Thyroid Gland ◽

Structural Changes ◽

Structure And Function ◽

Initial Increase ◽

Histological Structure ◽

Pituitary Thyroid Axis ◽

Thyroid Axis ◽

And Function ◽

Sexually Mature

The pituitary-thyroid axis of young sexually mature rabbits kept under a 24-hour daylight photoperiod was shown to undergo phase-modulated variations of hormonal activity with its initial increase (during the first month) and subsequent progressive decrease (within 2-5 months after the onset of exposure to light). These changes correlated with the time-dependent fall in the blood T3, T4, and TSH levels. Simultaneously, the animals developed pathological changes in the histological structure of the thyroid gland similar to those in patients with secondary or tertiary hypothyroidism. It is concluded that hormonal and structural changes in the thyroid gland during long-term hypopinealism should be regarded as an experimental model of hypothyroidism of neuroendocrine origin.

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Abstract 2468: Is the LV Reverse Remodeling Imparted by Aortic Valve Replacement for Severe Aortic Stenosis Durable? A Cardiovascular MRI Study sponsored by the American Heart Association

Circulation ◽

10.1161/circ.116.suppl_16.ii_543-b ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Robert W Biederman ◽

James A Magovern ◽

Saundra Grant ◽

Ronald Williams ◽

June Yamrozik ◽

...

Keyword(s):

Aortic Valve ◽

Aortic Stenosis ◽

Aortic Valve Replacement ◽

Severe Aortic Stenosis ◽

Structure And Function ◽

Reverse Remodeling ◽

Beneficial Effects ◽

And Function ◽

Surgically Induced

Background In patients with severe aortic stenosis (AS), long-term data tracking surgically induced beneficial effects of afterload reduction on reverse LV remodeling are not available. Echocardiographic data is available short term, but in limited fashion beyond one year. Cardiac MRI (CMR) offers the ability to track changes in LV metrics with small numbers due to its inherent high spatial resolution and low variability. Hypothesis We hypothesize that progressive changes following aortic valve replacement (AVR) are detectable by CMR and changes in LV structure and function, triggered by AVR, continue for an extended period following AVR. Methods Ten patients (67±12 yrs, 6 female) with severe, but compensated AS, underwent CMR pre-AVR and post AVR at 6±2mo, 1yr±2mo, 4yrs±5mo. LV mass index (LVMI), LV geometry, volumetrics and EF were measured (GE, EXCITE 1.5T, Milwaukee, WI). A Kruskall-Wallis one-way ANOVA was performed. Results All 10 pts survived AVR and underwent CMR at the 4-year time point (40 total time points). LVMI markedly decreased at 6 months (157±42 to 134±32g/m 2 , p<0.005) and continued to trend down at 4 yrs (127±32g/m 2 ). Similarly, EF increased pre to post AVR (55±22 to 65±11%, (p<0.05)) and continued trending upward, remaining stable at years 1–4 (66±11 vs. 65±9%). LVEDV index, initially high pre AVR, normalized post AVR (83±30 to 68±11ml/m 2 , p<0.05) trending even lower by yr 4 (66±10 ml/m 2 ). LV stroke volume increased rapidly from pre to post AVR (40±11 to 44±7ml) continuing to increase at 4 yrs (49±14ml, p=0.3). Most importantly, LVMI/volume, a 3D measure of LV geometry, remained unchanged initially but over 4 yrs markedly improved (1.07±0.2 to 0.94±0.24, p<0.05) all paralleling improvements in NYHA (3.2±1.0 to 1.5±1.1, p<0.05). Conclusion After the initial beneficial effects imparted by AVR in severe AS patients, there are, as expected, marked improvements in LV reverse remodeling. We have shown, via CMR, that surgically induced benefits to LV structure and function, including favorable alterations in LV geometry, are durable and, unexpectedly, show continued improvement past 4 years concordant with sustained improved clinical status. This supports down regulation of both mRNA and MMP activity acutely and robust suppression long term.

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