Abnormal bone mineral metabolism after long-term anticonvulsant treatment

Osteoporotic fracture and parathyroid hormone

Osteoporosis and age-related bone loss is associated with changes in bone remodeling characterized by decreased bone formation relative to bone resorption, resulting in bone fragility and increased risk of fractures. Stimulating the function of bone-forming osteoblasts, is the preferred pharmacological intervention for osteoporosis. Recombinant parathyroid hormone (PTH), PTH(1-34), is an anabolic agent with proven benefits to bone strength and has been characterized as a potential therapy for skeletal repair. In spite of PTH's clinical use, safety is a major consideration for long-term treatment. Studies have demonstrated that intermittent PTH treatment enhances and accelerates the skeletal repair process via a number of mechanisms. Recent research into the molecular mechanism of PTH action on bone tissue has led to the development of PTH analogs to control osteoporotic fractures. This review summarizes a number of advances made in the field of PTH and bone fracture to combat these injuries in humans and in animal models. The ultimate goal of providing an alternative to PTH, currently the sole anabolic therapy in clinical use, to promote bone formation and improve bone strength in the aging population is yet to be achieved.

Hypocalcemia in children: pathogenesis and management

Hypocalcemia can be devastating if unrecognized. Neuromuscular dysfunction occurs in severe cases. A review and an update on the topic may assist general pediatricians. The authors provide a general overview of pathogenesis and management of hypocalcemia in children.

Changes in bone turnover and deoxypyridinoline levels in epileptic patients

In this study, we evaluated bone turnover in 52 epileptic patients receiving chronic anticonvulsant therapy and in 39 healthy volunteers whose ages matched those of the patients. We determined serum osteocalcin and total and bone alkaline phosphatase levels as markers of bone formation, and urinary deoxypyridinoline and urinary calcium levels as markers of bone resorption. Statistical comparison of the levels of these markers between sexes in epileptic patients and their control groups revealed that total alkaline phosphatase levels were significantly increased in patients from both sexes compared with those of their controls. Urinary deoxypyridinoline levels of male epileptic patients were significantly increased compared with those of their controls. On the other hand, 25-hydroxyvitamin D levels of the male patients were significantly reduced compared with those of their controls. Serum osteocalcin, bone alkaline phosphatase, and urinary calcium levels of epileptic patients were not statistically different from those of the controls. We found that urinary deoxypyridinoline levels of male epileptic patients were increased, however, we observed no difference in serum osteocalcin and bone alkaline phosphatase levels. The lack of difference may be attributed to the fact that only the resorption phase of bone turnover is affected during chronic anticonvulsant therapy.

Experimental models for evaluating enzyme induction potential of new drug candidates in animals and humans and a strategy for their use

Experimental models that have application for evaluating enzyme induction potential have been described in order of increasing complexity. The main focus was on models that have had wide application thus far. However, many new models are currently being developed that may have future applications in evaluating enzyme induction potential. A strategy to evaluate the enzyme induction potential of drug candidates was outlined. This scheme uses a combination of new and established techniques to evaluate data in a stepwise manner that is appropriate to the drug's current stage of development.