BackgroundSodium butyrate (NaB) is a histone deacetylase (HDAC) inhibitor exhibiting anti-inflammatory and neuroprotective effects in a rat ischemic model of stroke as well as a myocardial ischemia model. Although clinical evidence shows that older women are at higher risk for stroke occurrence and greater stroke severity, no studies have evaluated the effectiveness of NaB either in females or in older animals.MethodsTo determine the effects of NaB on stroke in older females, acyclic middle-aged Sprague-Dawley female rats (9–11 months old, constant diestrus) were subject to middle cerebral artery occlusion (MCAo) by intracerebral injection of recombinant endothelin-1. Rats were treated with NaB (300 mg/kg, i.p.) at 6 and 30 h following ET-1 injection. Animals were sacrificed at the early (2 days) or late (5 days) acute phase after MCAo. Serum and tissue lysates were collected for biochemical analyses.ResultsNaB treatment reduced infarct volume and ameliorated sensory motor impairment in middle-aged female rats, when measured at 2 and 5 days post MCAo. At the early acute phase (2 days post stroke), NaB treatment decreased brain lipid peroxides, and reduced serum levels of GFAP, a surrogate marker of blood-brain barrier (BBB) permeability. NaB also reduced expression of the inflammatory cytokine IL-1beta in circulation and IL-18 in the ischemic hemisphere. At the late acute phase (5 days post stroke), NaB treatment further suppressed MCAo-induced increase of IL-1beta, IL-17A, and IL-18 in brain lysates (cortex and striatum) from the ischemic hemisphere, and decreased ischemia-induced upregulation of IL-1beta and IL-18 in circulation, indicating a potent anti-inflammatory effect of the HDAC inhibitor. Moreover, NaB treatment also increased expression of IGF-1, a known neuroprotectant, in peripheral tissue including serum, liver, and spleen at the late acute phase.ConclusionsThese data provide the first evidence that delayed (>6 h) NaB treatment post-stroke is neuroprotective in older female rats. Additionally, these data also show that in addition to its well-known anti-inflammatory actions, NaB may exert a biphasic effect after stroke, operating initially to reduce BBB permeability and oxidative stress in the brain, and later, elevating IGF-1 expression in peripheral tissues.

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Rett syndrome (RTT) is an autism spectrum disorder (ASD) caused by mutations in the X-linked MECP2 gene that encodes methyl-CpG binding protein 2 (MeCP2). Symptoms range in severity and include psychomotor disabilities, seizures, ataxia, and intellectual disability. Symptom onset is between 6-18 months of age, a critical period of brain development that is highly energy-dependent. Notably, patients with RTT have evidence of mitochondrial dysfunction, as well as abnormal levels of the adipokines leptin and adiponectin, suggesting overall metabolic imbalance. We hypothesized that one contributor to RTT symptoms is energy deficiency due to defective nutrient substrate utilization by the TCA cycle. This energy deficit would lead to a metabolic imbalance, but would be treatable by providing anaplerotic substrates to the TCA cycle to enhance energy production. We show that dietary therapy with triheptanoin significantly increased longevity and improved motor function and social interaction in male mice hemizygous for Mecp2 knockout. Anaplerotic therapy in Mecp2 knockout mice also improved indicators of impaired substrate utilization, decreased adiposity, increased glucose tolerance and insulin sensitivity, decreased serum leptin and insulin, and improved mitochondrial morphology in skeletal muscle. Untargeted metabolomics of liver and skeletal muscle revealed increases in levels of TCA cycle intermediates with triheptanoin diet, as well as normalizations of glucose and fatty acid biochemical pathways consistent with the improved metabolic phenotype in Mecp2 knockout mice on triheptanoin. These results suggest that an approach using dietary supplementation with anaplerotic substrate is effective in improving symptoms and metabolic health in RTT.

There are numerous techniques for the surgical management of thumb carpometacarpal (CMC) joint arthritis. The four senior authors of this study employ three such techniques: trapeziectomy with hematoma distraction arthroplasty, hemitrapeziectomy with osteochondral allograft, and ligament reconstruction tendon interposition (LRTI). This study examines the three commonly utilized procedures at a single institution. This study examines the 10-year experience from 1995-2005 with a minimum 3-month follow-up. Disabilities of the arm, shoulder, and hand (DASH) scores, pre-and postoperative pinch strength, and operative time were examined. After approval from the institutional review board of our institution was obtained, all patients treated surgically by three of the senior authors were contacted via mail and phone. Each patient was asked to complete and return a DASH questionnaire. Of the 115 patients treated during that period, 60 participated in this study. Each patient's final postoperative pinch measurement was obtained from occupational therapy and clinic records. This pinch strength was compared to the preoperative pinch and contralateral pinch strength. Lastly, the total operative time for each procedure was obtained from the operative record. The only significant finding in this study was a shorter mean operative time with the trapeziectomy group (76.90 min) and osteochondral allograft group (90.45 min) when compared to the LRTI group (139.00 min; p = 0.001 and p = 0.001, respectively). We found no significant difference between groups in terms of DASH score and pinch strength. There was no difference between the techniques in terms of postoperative pinch strength and patient satisfaction measured by DASH scores. The operative times for trapeziectomy and hematoma interposition as well as the osteochondral allograft were significantly shorter than that of the LRTI. This presents further evidence that potentially, "less is more" in the treatment of thumb CMC arthritis. We used a retrospective study design to evaluate potential differences between the three surgical techniques described above, therapeutic, levels III-IV.

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In animal models, middle-aged females sustain greater ischemia-induced infarction as compared to adult females. This age difference in infarct severity is associated with reduced functional capacity of astrocytes, a critical neural support cell. The impaired response of astrocytes following stroke in middle-aged females may be related to epigenetic alterations, including histone acetylation or methylation. The present study measured the activity of enzymes that regulate histone acetylation and methylation in cerebral cortical astrocytes of adult (6 month) and middle-aged (11+ month) female rats 48 h following middle cerebral artery occlusion. H3K4 histone methyltransferase activity was decreased in astrocytes from middle-aged females. The next experiment therefore examined H3K4me3 (transcriptional enhancer) and H3K9me3 (transcriptional repressor) in astrocytes from adult and middle-aged females using ChIP-seq analysis. Adult females had more enriched H3K4me3 peaks (304 vs. 26) at transcriptional start sites and fewer H3K9me3 enriched peaks than middle-aged females (4 vs. 22), indicating a pattern of less active chromatin in astrocytes in the older group following ischemia. DAVID clustering analysis of H3K4me3 enriched genes found several functional categories, including cell motility, regulation of apoptosis and the vascular endothelial growth factor (VEGF) pathway. H3K4me3 was enriched at the miR-17-20 cluster and VEGFa, and analysis of a separate set of astrocytes confirmed that VEGF protein expression and miR-20 mRNA expression were significantly greater following ischemia in adult females compared to middle-aged females. These data indicate that astrocytes display less active chromatin with aging and provide new insight into possible mechanisms for differences in stroke severity observed during aging.

The incidence of type 2 diabetes (T2D) is rapidly expanding. Some of the more obvious pathologies associated with it include: defective glucose metabolism, obesity, cardiovascular disease and an inability to mount an effective immune response to infection by certain pathogenic organisms, leading to sepsis and death. A common tie linking these seemingly disparate complications is chronic inflammation. Today we know that inflammation is regulated locally and systemically by numerous biochemical signals. One of the most important of these signals is a class of molecules called cytokines. Cytokines can be generally classified as proinflammatory or anti-inflammatory and allow an organism to respond rapidly to an immune challenge by coordinating an appropriate immune response. In T2D, the balance between proinflammatory and anti-inflammatory cytokines is shifted toward proinflammation, potentially causing or exacerbating the health complications found in T2D. Over-nutrition has been shown to trigger the innate immune system but activation of the innate immune system, itself, induces hyperglycemia and insulin resistance. In all likelihood, diabetes and chronic inflammation are inseparable and act as a reciprocal feed-forward loop.