muscle biopsies in healthy volunteers

Conditions: Sarcopenia; Frailty; Aging

Summary: background: - in individuals as they age, changes in muscle tissue can significantly affect their muscle strength and exercise endurance. this process, known as sarcopenia, may lead to decreased mobility and physical weakness, which is what we in general refer to as frailty. the causes of sarcopenia and why it affects some individuals more than others are not known, but many factors influence muscle physiology and function, including metabolic, hormonal, environmental, and lifestyle factors. researchers interested in identifying factors involved in the start and progression of sarcopenia need of samples of human muscle tissue and cells for laboratory investigations. objectives: * to train researchers in the appropriate procedures for performing muscle biopsies and collecting, labeling, and storing the samples. * develop a data base of specific scientific studies evaluating the physiological and metabolic function of muscle that can be used in future studies. eligibility: - healthy volunteers at least 18 years of age. design: * participants will be screened with a full medical history and physical examination, as well as blood and urine tests, and will schedule a date for the muscle biopsy. * participants will have a muscle biopsy, with tissue and cells taken from the upper part of the thigh. a local anesthetic will be given for the procedure. participants will also provide a blood sample and have an electrocardiogram to evaluate heart function. * participants will have a followup visit 1 week after the biopsy visit to evaluate the healing process and provide any further treatment for the affected area, after which they may fully resume normal activities.

an important concept in pathologic aging is that in some individuals muscle strength and exercise endurance are significantly decreased through both quantitative and qualitative changes in muscle tissue. this process, termed sarcopenia, leads to frailty, a syndrome characterized by decreased mobility, weakness, and a very poor prognosis for survival, although the causal pathway for this association is not known. the causes of sarcopenia and why it affects some individuals more than others is not known. this is a complicated scientific question because many factors influence muscle physiology and function, including metabolic, hormonal, environmental, life-style, co-morbid medical problems and their treatments, etc. the national institute on aging (nia) has a long-standing interest in sarcopenia and frailty and has established a number of observational studies aimed at understanding the cause and course of these age-related conditions. it is our goal to try to identify factors involved in the initiation and progression of sarcopenia and frailty, and to develop therapies that can reverse or slow these processes. to identify molecular and genetic changes that are associated with sarcopenia, it is crucial that human muscle biopsy specimens be available for laboratory investigations. this proposal will enable the clinical research branch (crb) to set up this procedure on the nia clinical research unit located on the fifth floor at harbor hospital, and to hone the practical skills that will be needed for analyzing muscle tissue from individuals in observational and interventional clinical trials. the goal will be to become facile at performing muscle biopsies, collecting, labeling and storing the samples, and to ensure that all equipment and expertise required to efficiently perform the procedure are in place. 14 healthy volunteers will be accrued to the study, however after this, the protocol will be kept open for the purpose of training other physicians or nurse practitioners in the biopsy procedure.

Eligibility criteria:
* inclusion criteria: healthy volunteers over the age of 18 normal screening laboratory studies including cbc, chem. 12 panel, pt/ptt, inr, ua, ekg ability to provide informed consent exclusion criteria: no history of bleeding diathesis subject is not on heparin, coumadin, plavix, or other anticoagulant subjects taking aspirin or non-steroidal anti-inflammatory agents must stop these 7 days before the biopsy no allergy to lidocaine or bupivacaine subject has no active infections or chronic skin conditions that prevent access to the biopsy area unable to provide informed consent no antibiotics for the past week positive pregnancy test positive for hiv, and/or positive for hepatitis b or c

Keywords: muscle biopsy energetics sarcopenia frailty