Proteases play a critical role in many of the physiologic processes of wound repair. However, if their activity becomes uncontrolled proteases can mediate devastating tissue damage and consequently they have been implicated in chronic wound pathophysiology. Previous studies have shown that chronic wound fluid contains elevated protease levels that have deleterious effects, degrading de novo granulation tissue and endogenous biologically active proteins such as growth factors and cytokines. Therefore, we have proposed that an effective therapeutic approach for chronic wounds would be to modify this hostile environment and redress this proteolytic imbalance. Using an ex vivo wound fluid model, we show the ability of a proprietary new wound treatment to bind and inactivate proteases. We have shown that the addition of this test material to human chronic wound fluid obtained from diabetic foot ulcer patients resulted in a significant reduction in the activities of neutrophil-derived elastase, plasmin, and matrix metalloproteinase when compared to wet gauze. This study provides mechanistic evidence to support the hypothesis that this novel treatment modality for chronic wounds physically modifies the wound microenvironment, and thereby promotes granulation tissue formation and stimulates wound repair.

Creatine is an endogenous compound synthesized from arginine, glycine and methionine. This dietary supplement can be acquired from food sources such as meat and fish, along with athlete supplement powders. Since the majority of creatine is stored in skeletal muscle, dietary creatine supplementation has traditionally been important for athletes and bodybuilders to increase the power, strength, and mass of the skeletal muscle. However, new uses for creatine have emerged suggesting that it may be important in preventing or delaying the onset of neurodegenerative diseases associated with aging. On average, 30% of muscle mass is lost by age 80, while muscular weakness remains a vital cause for loss of independence in the elderly population. In light of these new roles of creatine, the dietary supplement’s usage has been studied to determine its efficacy in treating congestive heart failure, gyrate atrophy, insulin insensitivity, cancer, and high cholesterol. In relation to the brain, creatine has been shown to have antioxidant properties, reduce mental fatigue, protect the brain from neurotoxicity, and improve facets/components of neurological disorders like depression and bipolar disorder. The combination of these benefits has made creatine a leading candidate in the fight against age-related diseases, such as Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, long-term memory impairments associated with the progression of Alzheimer’s disease, and stroke. In this review, we explore the normal mechanisms by which creatine is produced and its necessary physiology, while paying special attention to the importance of creatine supplementation in improving diseases and disorders associated with brain aging and outlining the clinical trials involving creatine to treat these diseases.

Acid-sensing ion channels (ASICs) evolved to sense changes in extracellular acidity with the divalent cation calcium (Ca2+) as an allosteric modulator and channel blocker. The channel-blocking activity is most apparent in ASIC3, as removing Ca2+ results in channel opening, with the site’s location remaining unresolved. Here we show that a ring of rat ASIC3 (rASIC3) glutamates (Glu435), located above the channel gate, modulates proton sensitivity and contributes to the formation of the elusive Ca2+ block site. Mutation of this residue to glycine, the equivalent residue in chicken ASIC1, diminished the rASIC3 Ca2+ block effect. Atomistic molecular dynamic simulations corroborate the involvement of this acidic residue in forming a high-affinity Ca2+ site atop the channel pore. Furthermore, the reported observations provide clarity for past controversies regarding ASIC channel gating. Our findings enhance understanding of ASIC gating mechanisms and provide structural and energetic insights into this unique calcium-binding site.

Previous place conditioning studies in mice have shown that injection of ethanol immediately before a conditioned stimulus (CS+) produces conditioned preference, whereas injection of ethanol immediately after CS+ produces conditioned aversion. In the present experiments, we examined the learning that occurs when ethanol is injected in "ambiguous" procedures that provide the opportunity for both types of conditioning. When ethanol was given midway through the CS (Experiments 1 and 2) or both before and after the CS (Experiment 3), the direction of place conditioning was the same as when mice were exposed only to whichever contingency occurred first (a primacy effect). That is, injection of ethanol in the middle of the CS conditioned aversion, whereas injection both before and after the CS conditioned preference. Because these results support the idea that ethanol elicits both aversive and rewarding effects, they are most consistent with conditioning theories that conceptualize unconditioned stimuli (USs) as events that can activate multiple representational components.

Osteoporosis is a common disease with a strong genetic component, characterized by reduced bone mineral density and increased fracture risk. Although the genetic basis of osteoporosis is incompletely understood, previous studies have identified a polymorphism affecting an Sp1 binding site in the COLIA1 gene that predicts bone mineral density and osteoporotic fractures in several populations. Here we investigated the role of COLIA1 genotyping and bone densitometry in the prediction of osteoporotic fractures in a prospective, population-based study of men (n = 156) and women (n = 185) who were followed up for a mean (+/- SEM) of 4.88+/-0.03 years. There was no significant difference in bone density, rate of bone loss, body weight, height, or years since menopause between the genotype groups but women with the 'ss' genotype were significantly older than the other genotype groups (p = 0.03). Thirty-nine individuals sustained 54 fractures during follow-up and these predominantly occurred in women (45 fractures in 30 individuals). Fractures were significantly more common in females who carried the COLIA1 's' allele (p = 0.001), although there was no significant association between COLIA1 genotype and the occurrence of fractures in men. Logistic regression analysis showed that carriage of the COLIA1 's' allele was an independent predictor of fracture in women with an odds ratio (OR) [95% CI] of 2.59 [1.23-5.45], along with spine bone mineral density (OR = 1.57 [1.04-2.37] per Z-score unit) and body weight (OR = 1.05 [1.01-1.10] per kilogram). Moreover, bone densitometry and COLIA1 genotyping interacted significantly to enhance fracture prediction in women (p = 0.01), such that the incidence of fractures was 45 times higher in those with low BMD who carried the 's' allele (24.3 fractures/100 patient-years) compared with those with high BMD who were 'SS' homozygotes (0.54 fracture/100 patient-years). We conclude that in our population, COLIA1 genotyping predicts fractures independently of bone mass and interacts with bone densitometry to help identify women who are at high and low risk of sustaining osteoporotic fractures.