Effects of pro-inflammatory cytokines on cannabinoid CB1 and CB2 receptors in immune cells.

AIMS: To investigate the regulation of cannabinoid receptors CB1 and CB2 on immune cells by pro-inflammatory cytokines and its potential relevance to the inflammatory neurological disease, multiple sclerosis (MS). CB1 and CB2 signalling may be anti-inflammatory and neuroprotective in neuroinflammatory diseases. Cannabinoids can suppress inflammatory cytokines but the effects of these cytokines on CB1 and CB2 expression and function are unknown. METHODS: Immune cells from peripheral blood were obtained from healthy volunteers and patients with MS. Expression of CB1 and CB2 mRNA in whole blood cells, peripheral blood mononuclear cells (PBMC) and T cells was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Expression of CB1 and CB2 protein was determined by flow cytometry. CB1 and CB2 signalling in PBMC was determined by Western blotting for Erk1/2. RESULTS: Pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α (the latter likely NF-κB dependently) can upregulate CB1 and CB2 on human whole blood and peripheral blood mononuclear cells (PBMC). We also demonstrate upregulation of CB1 and CB2 and increased IL-1ß, IL-6 and TNF-α mRNA in blood of patients with MS compared with controls. CONCLUSION: The levels of CB1 and CB2 can be upregulated by inflammatory cytokines, which can explain their increase in inflammatory conditions including MS.

The effect of a short sprint on postexercise whole-body glucose production and utilization rates in individuals with type 1 diabetes mellitus.

CONTEXT: Recently we showed that a 10-sec maximal sprint effort performed before or after moderate intensity exercise can prevent early hypoglycemia during recovery in individuals with type 1 diabetes mellitus (T1DM). However, the mechanisms underlying this protective effect of sprinting are still unknown. OBJECTIVE: The objective of the study was to test the hypothesis that short duration sprinting increases blood glucose levels via a disproportionate increase in glucose rate of appearance (Ra) relative to glucose rate of disappearance (Rd). SUBJECTS AND EXPERIMENTAL DESIGN: Eight T1DM participants were subjected to a euglycemic-euinsulinemic clamp and, together with nondiabetic participants, were infused with [6,6-(2)H]glucose before sprinting for 10 sec and allowed to recover for 2 h. RESULTS: In response to sprinting, blood glucose levels increased by 1.2 ± 0.2 mmol/liter (P < 0.05) within 30 min of recovery in T1DM participants and remained stable afterward, whereas glycemia rose by only 0.40 ± 0.05 mmol/liter in the nondiabetic group. During recovery, glucose Ra did not change in both groups (P > 0.05), but glucose Rd in the nondiabetic and diabetic participants fell rapidly after exercise before returning within 30 min to preexercise levels. After sprinting, the levels of plasma epinephrine, norepinephrine, and GH rose transiently in both experimental groups (P < 0.05). CONCLUSION: A sprint as short as 10 sec can increase plasma glucose levels in nondiabetic and T1DM individuals, with this rise resulting from a transient decline in glucose Rd rather than from a disproportionate rise in glucose Ra relative to glucose Rd as reported with intense aerobic exercise.

Postdetonation nuclear debris for attribution.

On the morning of July 16, 1945, the first atomic bomb was exploded in New Mexico on the White Sands Proving Ground. The device was a plutonium implosion device similar to the device that destroyed Nagasaki, Japan, on August 9 of that same year. Recently, with the enactment of US public law 111-140, the "Nuclear Forensics and Attribution Act," scientists in the government and academia have been able, in earnest, to consider what type of forensic-style information may be obtained after a nuclear detonation. To conduct a robust attribution process for an exploded device placed by a nonstate actor, forensic analysis must yield information about not only the nuclear material in the device but about other materials that went into its construction. We have performed an investigation of glassed ground debris from the first nuclear test showing correlations among multiple analytical techniques. Surprisingly, there is strong evidence, obtainable only through microanalysis, that secondary materials used in the device can be identified and positively associated with the nuclear material.

Glucocorticoids increase CD4CD25 cell percentage and Foxp3 expression in patients with multiple sclerosis.

OBJECTIVES: To determine whether percentages of CD4(+)CD25(high) T cells (a group of regulatory T cells, Treg) differ in patients with multiple sclerosis (MS) in relapse vs remission after glucocorticoid treatment and whether treatment for relapses changes Treg population and the expression of Foxp3, a key Treg-associated molecule. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from 20 patients with MS during relapse, just before and 2 days after starting steroid treatment (i.v. methylprednisolone 1 g/day for 3 days) and then 6 weeks after treatment. CD4(+)CD25(hi) cells were analysed by using flow cytometry. Cytokines were measured by using an ELISA and Foxp3, CD3 and CD25 expression by using quantitative real-time PCR. RESULTS: The percentage of CD4(+)CD25(hi) cells, plasma IL-10 and Foxp3/CD3 ratio increased 48 h after methylprednisolone initiation and returned to baseline values by 6 weeks post-treatment. CONCLUSIONS: Results suggest that glucocorticoids increase Treg cell functional molecules and percentages. This may be a mechanism whereby steroids expedite recovery from MS relapses.

The effect of maternal undernutrition before muscle differentiation on the muscle fiber development of the newborn lamb.

There is a need to improve the lean tissue content of ruminant animals destined for meat production. Muscle fiber number is set during fetal development. The effect of undernutrition of pregnant ewes on subsequent muscle fiber characteristics of their offspring was investigated. The trial involved 32 pregnant ewes carrying twins. The ewes were allocated randomly to one of four groups: three different treatment groups (n = 8) and a control group (n = 8). The diet of the treatment groups was dropped to 50% of their daily requirement to support the ewe and allow for conceptus growth for varying periods before being returned to 100% of their daily requirement until term. Group d 30-70 ewes were fed 100% of their daily requirement until d 30, the diet was then decreased to 50% until d 70; it was then returned to 100% of their daily requirement until term. Group d 55-95 ewes were similarly restricted from d 55 through 95, and Group d 85-115 ewes were restricted from d 85 through 115. The control group was fed 100% of their daily requirement to support the ewe and allow for conceptus growth throughout gestation. After parturition, the lactating ewes were fed a normal commercial diet. On d 14 (after parturition), the lambs were slaughtered and the LM, semitendinosus (ST), and vastus lateralis (VL) were dissected and snap frozen. The immunochemical determination of myosin heavy-chain slow (MHC-slow) and myosin heavy-chain fast (MHC-fast) proteins was measured by immunoprobing of Western blots. The number of fast and slow fibers and the diameter of these fibers also were measured in each muscle sample by histochemical techniques. Decreased maternal nutrition before fiber formation (d 30 through 70) was observed to change the muscle characteristics of the newborn lambs. These lambs had significantly fewer fast fibers (P < 0.001) and significantly more slow fibers (P < 0.001) in both the LM and VL compared with the other groups. Maternal nutrient restriction at the other periods had no effect on the number of muscle fibers in the newborn lambs; however, a decrease (LM, P < 0.05; VL, P < 0.01; ST, P = 0.08) in muscle weight was observed in the lambs born to the ewes restricted between d 85 and 115 of gestation compared with the other groups. This study has shown that decreased maternal diet before muscle fiber formation will alter the muscle fiber development in the fetus.

Ontogeny of factors associated with proliferation and differentiation of muscle in the ovine fetus.

The number of muscle fibers within a muscle has been found to be of high importance for the growth potential of an animal, and this number is set during fetal development. The objective of this study was to identify the ontogeny of muscle cell differentiation and fiber formation by observing the changes in expression of factors known to influence myoblast proliferation and differentiation. Twenty-one Swaledale x Leicester Blue Face ewes carrying twins were allotted to this trial. From d 40 of gestation, three ewes were killed every 15 d until term. At each time point, the fetuses were located, removed, and total muscle from both hind limbs was dissected from each fetus and snap frozen in liquid N2. Ribonuclease protection assays were used to quantify transcripts for IGF-I, IGF-II, GH receptor (GHR), and myostatin genes in the muscle samples, whereas quantitative real-time PCR was used to quantify myogenin transcripts. Histological sections also were taken from the fetal muscle samples and observed for evidence of muscle differentiation resulting in fiber formation. The abundance of mRNA for ovine IGF-II and ovine myogenin peaked at d 85 of gestation (P < 0.001). The abundance of ovine IGF-I transcripts peaked at d 100 of gestation, whereas the abundance of ovine GHR mRNA increased throughout gestation (P < 0.05). No change (P = 0.87) in the abundance of myostatin mRNA was observed. The histological sections from the muscle samples demonstrated a clear change in the appearance of the muscle tissue at each time period. Major fiber formation was observed around d 85. The results obtained from the analysis of gene expression and the histological sections suggest that the majority of muscle differentiation and fiber formation takes place around d 85, with myoblast proliferation mainly occurring before this time. It may be possible to manipulate the number of muscle fibers formed by targeting treatments during this proliferation stage immediately before the period of major fiber formation.