Amyotrophic lateral sclerosis: delayed disease progression in mice by treatment with a cannabinoid.

Effective treatment for amyotrophic lateral sclerosis (ALS) remains elusive. Two of the primary hypotheses underlying motor neuron vulnerability are susceptibility to excitotoxicity and oxidative damage. There is rapidly emerging evidence that the cannabinoid receptor system has the potential to reduce both excitotoxic and oxidative cell damage. Here we report that treatment with Delta(9)-tetrahydrocannabinol (Delta(9)-THC) was effective if administered either before or after onset of signs in the ALS mouse model (hSOD(G93A) transgenic mice). Administration at the onset of tremors delayed motor impairment and prolonged survival in Delta(9)-THC treated mice when compared to vehicle controls. In addition, we present an improved method for the analysis of disease progression in the ALS mouse model. This logistic model provides an estimate of the age at which muscle endurance has declined by 50% with much greater accuracy than could be attained for any other measure of decline. In vitro, Delta(9)-THC was extremely effective at reducing oxidative damage in spinal cord cultures. Additionally, Delta(9)-THC is anti-excitotoxic in vitro. These cellular mechanisms may underlie the presumed neuroprotective effect in ALS. As Delta(9)-THC is well tolerated, it and other cannabinoids may prove to be novel therapeutic targets for the treatment of ALS.

Clinical case seminar: Riedel's thyroiditis: report of a case complicated by spontaneous hypoparathyroidism, recurrent laryngeal nerve injury, and Horner's syndrome.

A 42-yr-old woman presented with hyperthyroidism and a large, firm, irregular goiter. Within a few weeks she became hypothyroid. Five months later she developed increasingly severe neck pain and compressive symptoms. The goiter had become rock hard. A fine needle aspiration biopsy showed features of chronic thyroiditis and fibrosis. She partially responded to a course of glucocorticoids. Tamoxifen was added, with marked improvement in goiter size and pain. Both medications were tapered off. Two months later the patient experienced paresthesias of the fingertips, perioral numbness, and a seizure. She was found to have spontaneous primary hypoparathyroidism. Three months later the patient became hoarse and experienced difficulty in breathing. She was found to have a massively enlarged thyroid with compression of the right internal jugular vein and encasement of the right carotid artery as well as tracheal narrowing. She also had right vocal cord paralysis due to recurrent laryngeal nerve involvement. Because of airway compromise, an emergency isthmusectomy was performed, and the patient was given a postoperative course of glucocorticoids with gradual improvement. Postoperative diagnosis was Riedel's thyroiditis. Two months later she presented with near-syncope and was found to have bradycardia, hypotension, and right Horner's syndrome, presumably due to compression of the right carotid sheath. She was given i.v. glucocorticoids and tamoxifen. Six months later and 18 months after her initial presentation, the patient is doing remarkably well. Her goiter has regressed by more than 50%, and she no longer has any pain or difficulty breathing. She remains a little hoarse and has persistent hypothyroidism and hypoparathyroidism. She is taking prednisone (5 mg, this is being tapered very slowly) and tamoxifen (20 mg) daily. This case illustrates the protean manifestations of Riedel's thyroiditis, a rare but fascinating disease. The epidemiology of this disease, its pathophysiology and complications, and the roles of surgery and medical therapy are reviewed.