Cardio-protective effects of carnitine in streptozotocin-induced diabetic rats

BACKGROUND: Streptozotocin-induced diabetes (STZ-D) in rats has been associated with carnitine deficiency, bradycardia and left ventricular enlargement. AIM: The purpose of this study was to determine whether oral carnitine supplementation would normalize carnitine levels and cardiac function in STZ-D rats. METHODS: Wistar rats (48) were made hyperglycemic by STZ at 26 weeks of age. Same age normal Wistar rats (24) were used for comparison. Echocardiograms were performed at baseline 2, 6, 10, and 18 weeks after STZ administration in all animals. HbA1c, serum carnitine and free fatty acids (FFA) were measured at the same times. Since STZ-D rats become carnitine deficient, 15 STZ-D rats received supplemental oral carnitine for 16 weeks. RESULTS: The heart rates for the STZ-D rats (290 ± 19 bpm) were less than control rats (324 ± 20 bpm) (p < 0.05). After 4 weeks of oral carnitine supplementation, the serum carnitine and heart rates of the STZ-D rats returned to normal. Dobutamine stress increased the heart rates of all study animals, but the increase in STZ-D rats (141 ± 8 bpm) was greater than controls (79 ± 8 bpm) (p < 0.05). The heart rates of STZ-D rats given oral carnitine, however, were no different than controls (94 ± 9 bpm). The left ventricular mass/body weight ratio (LVM/BW) in the diabetic animals (2.7 ± 0.5) was greater than control animals (2.2 ± 0.3) (p < 0.05) after 18 weeks of diabetes. In contrast, the LVM/BW (2.3 ± .2) of the STZ-D animals receiving supplemental carnitine was the same as the control animals at 18 weeks. CONCLUSION: Thus, supplemental oral carnitine in STZ-D rats normalized serum carnitine, heart rate regulation and left ventricular size. These findings suggest a metabolic mechanism for the cardiac dysfunction noted in this diabetic animal model

ACCF/AHA 2011 Expert Consensus Document on Hypertension in the Elderly: A Report of the American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents

This document was written with the intent to be a complete reference at the time of publication on the topic of managing hypertension in the elderly. This document has been developed as an expert consensus document by the American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA), in collaboration with the American Academy of Neurology (AAN), the American College of Physicians (ACP), the American Geriatrics Society (AGS), the American Society of Hypertension (ASH), the American Society of Nephrology (ASN), the American Society for Preventive Cardiology (ASPC), the Association of Black Cardiologists (ABC), and the European Society of Hypertension (ESH). Expert consensus documents are intended to inform practitioners, payers, and other interested parties of the opinion of ACCF and document cosponsors concerning evolving areas of clinical practice and/or technologies that are widely available or new to the practice community

ACCF/AHA 2011 Expert Consensus Document on Hypertension in the Elderly: A Report of the American College of Cardiology Foundation Task Force on Clinical Expert Consensus Documents

This document was written with the intent to be a complete reference at the time of publication on the topic of managing hypertension in the elderly. This document has been developed as an expert consensus document by the American College of Cardiology Foundation (ACCF) and the American Heart Association (AHA), in collaboration with the American Academy of Neurology (AAN), the American College of Physicians (ACP), the American Geriatrics Society (AGS), the American Society of Hypertension (ASH), the American Society of Nephrology (ASN), the American Society for Preventive Cardiology (ASPC), the Association of Black Cardiologists (ABC), and the European Society of Hypertension (ESH). Expert consensus documents are intended to inform practitioners, payers, and other interested parties of the opinion of ACCF and document cosponsors concerning evolving areas of clinical practice and/or technologies that are widely available or new to the practice community

The tailless ortholog nhr-67 functions in the development of the C. elegans ventral uterus

AbstractThe development of the C. elegans uterus provides a model for understanding the regulatory pathways that control organogenesis. In C. elegans, the ventral uterus develops through coordinated signaling between the uterine anchor cell (AC) and a ventral uterine (VU) cell. The nhr-67 gene encodes the nematode ortholog of the tailless nuclear receptor gene. Fly and vertebrate tailless genes function in neuronal and ectodermal developmental pathways. We show that nhr-67 functions in multiple steps in the development of the C. elegans uterus. First, it functions in the differentiation of the AC. Second, it functions in reciprocal signaling between the AC and an equipotent VU cell. Third, it is required for a later signaling event between the AC and VU descendants. nhr-67 is required for the expression of both the lag-2/Delta signal in the AC and the lin-12/Notch receptor in all three VU cells and their descendants, suggesting that nhr-67 may be a key regulator of Notch-signaling components. We discuss the implications of these findings for proposed developmental regulatory pathways that include the helix–loop–helix regulator hlh-2/daughterless and transcription factor egl-43/Evi1 in the differentiation of ventral uterine cell types